Phenology follow-up. Cicadas are coming!

Ezra's salamander

Ezra’s salamander

I wrote about phenology and shared our Twin Oaks phenology chart on 3/28. Since then I’ve read two related blogs I want to tell you about. One is my fellow Twin Oaker Ezra Freeman, whose blog ObserVa A year observing nature in Central Virginia has wonderful photos of plants and animals here at Twin Oaks and wherever he goes. Most recently a hike up Old Rag mountain in the Shenandoahs. The other is Chert Hollow Farm’s Bird list & other natural events. Eric and Joanna Reuter own and operate Chert Hollow Farm, a small, diversified farm featuring certified organic produce near Columbia, MO. They have a great website. Probably a thousand miles from Twin Oaks, so not the same as our backyard. In some ways that makes it all the more interesting. Another natural event I’m keeping tabs on is the emergence of the 17-year cicada. Debbie Roos  of the Growing Small Farms site posted a link to a news article about the coming emergence of Brood II of the 17-year periodical cicadas on her Facebook page and sent out a link to the Cooperative Extension’s Growing Small Farms website.

17 year cicada up close and personal

17 year cicada up close and personal. Credit Cicadamania.com

Cicada Mania is a great source for all cicada-related information.  The blog is amusing and packed with info. Adult cicadas begin to emerge when the soil temperatures reach 64F.  (My soil thermometer is monitoring temperature in a carrot bed I plan to flame-weed.) If you haven’t got a soil thermometer, Cicada Mania has an emergence calculator based on air temperature. http://www.cicadamania.com/cicadas/cicada-emergence-formula/ Here is a map of the areas which can expect to see this cicada, for a month or so, starting in May. We’re right in there. Adult female cicadas damage young woody plants by tunneling in thin twigs to lay eggs. I didn’t plant any new fruit bushes this past winter, so don’t really think I have much to worry about. Damage to older bushes and trees is dramatic-looking, but not usually permanently harmful. b_02

Phenology – What happens when

Flowering Purple (or Red) Dead Nettle, with honeybee.Credit Kathryn Simmons

Flowering Purple (or Red) Dead Nettle, with honeybee.
Credit Kathryn Simmons

For ten years I have been keeping phenology records, as a guide to when to plant certain crops, and as a way of tracking how fast the season is progressing.

Phenology involves tracking when certain wild and cultivated flowers bloom, seedlings emerge, or various insects are first seen. These natural events can substitute for Growing Degree Day calculations. Certain natural phenomena are related to the accumulated warmth of the season (rather than, say, the day-length), and by paying attention to nature’s calendar you will be in sync with actual conditions, which can vary from year to year, and are changing over a longer time-scale..

Many people know to sow sweet corn when oak leaves are the size of a squirrel’s ear. By this point, regardless of date, the season has warmed enough to get oak leaves to that size, which happens to be warm enough for sweet corn seed to germinate and grow well. Some people transplant eggplant, melons and peppers when irises bloom; sow fall brassicas when catalpas and mockoranges bloom; and know to look for squash vine borers laying eggs for the two weeks after chicory flowers. Some transplant tomatoes when the lily of the valley is in full bloom, or the daylilies start to bloom.

Lilac is often used to indicate when conditions are suitable for various plantings:

  •   When lilac leaves first form, plant potatoes
  •  When lilac is in first leaf (expanded), plant carrots, beets, brassicas, spinach, lettuce
  • When lilac is in early bloom, watch out for crabgrass germinating
  • When lilac is in full bloom, plant beans, squash, corn. Grasshopper eggs hatch.
  • When lilac flowers fade, plant cucumbers.

Also, recording the dates of the same biological events each year can show longer term climate changes. In Europe, 500 years of recorded dates of grape harvests provide information about summer temperatures during that time. Project Budburst is a citizen science field campaign to log leafing and flowering of native species of trees and flowers across the US each year. Each participant observes one or more species of plant for the whole season.

 Here’s our Twin Oaks Phenology Record so far:

(c) Pam Dawling, 2013

Event 2003 2004 2005 2006 2007 2008 2009 2010 2011 2012 2013 Notes
Crocus blooming 26-Jan 25-Jan 6-Feb 10-Feb 28-Feb 17-Feb 30-Jan
Chickweed blooming 8-Feb 1-Jan 5-Mar 10-Feb 13-Mar 19-Feb 13-Feb 15-Feb
Robins arrive 27-Feb 31-Jan 20-Jan 26-Feb 2-Mar 14-Feb
Henbit blooming 14-Mar 7-Mar 12-Jan 6-Jan 7-Feb 20-Feb 22-Mar 2-Mar 15-Feb 15-Feb
Daffodils blooming 17-Mar 9-Mar 7-Mar 1-Mar 22-Feb 3-Mar 5-Mar 15-Mar 3-Mar 17-Feb Plant potatoes
Dead-nettle blooming 18-Mar 6-Mar 7-Mar 8-Mar 14-Mar 9-Feb 24-Feb 13-Mar 21-Jan 22-Feb 10-Feb
Spring Peepers first heard 4-Mar 11-Mar 10-Mar 3-Mar 3-Mar 6-Mar 11-Mar 28-Feb 23-Feb 5-Mar Plant peas
Overwinter Grasshoppers seen 26-Feb 4-Apr 25-Feb
Maples Blooming 10-Mar 6-Mar 15-Mar 12-Mar 28-Feb
Dandelion blooming 16-Mar 16-Mar 24-Jan 1-Jan 3-Mar 17-Mar 9-Mar 8-Mar 19-Mar Sow beets, carrots
Forsythia blooming 13-Mar 12-Mar 28-Mar 10-Mar 23-Mar 13-Mar 17-Mar 21-Mar 15-Mar 12-Mar 15-Mar Plant peas. Crabgrass germinates.
Peach blooming 15-Mar 25-Mar 26-Mar 25-Mar 13-Mar
Cabbage White Butterfly 25-Mar 20-Mar 7-Mar 8-Mar 11-Mar 6-Apr 24-Mar 12-Mar 14-Mar Dutch white clover blooms
Harlequin bugs 10-Apr 13-Mar 26-Mar 12-May 16-Apr 29-Apr 14-Mar
Johnny Jump-up blooming 16-Mar 30-Mar 14-Mar 20-Mar 3-Apr 17-Mar
Flowering Cherry blooming 27-Mar 4-Apr 3-Apr 1-Apr 6-Apr 25-Mar 17-Mar 18-Mar 20-Mar
Asparagus spears 6-Apr 4-Apr 4-Apr 5-Apr 6-Apr 6-Apr 21-Mar 19-Mar
Redbud blooming 5-Apr 13-Apr 9-Apr 3-Apr 2-Apr 7-Apr 9-Apr 7-Apr 4-Apr 19-Mar Expect flea beetles
Smartweed germinating 15-Apr 10-Apr 15-Apr 6-Apr 11-Apr 1-Apr 23-Mar 20-Mar <149 GDD base 48F
Lambsquarters germinating 20-Mar 20-Mar <150 GDD base 48F
Violets blooming 29-Mar 26-Mar 28-Mar 6-Apr 22-Mar 20-Mar
Morning Glory germinating 27-Apr 10-Apr 3-Apr 26-Apr 24-Apr 25-Apr 22-Mar >349 GDD base 48F
Tiger Swallowtail 19-Apr 29-Mar 15-Apr 16-Apr 18-Apr 10-Apr 28-Mar
Apples blooming 18-Apr 20-Apr 14-Apr 7-Apr 12-Apr 28-Mar
Dogwood (Amer.) full bloom 5-Apr 21-Apr 13-Apr 28-Mar Plant peppers; soil 65 F
Strawberries bloom 13-Apr 11-Apr 14-Apr 12-Apr 4-Apr 2-Apr 15-Apr 6-Apr 8-Apr 30-Mar
Lilac full bloom 16-Apr 20-Apr 21-Apr 22-Apr 19-Apr 21-Apr 14-Apr 18-Apr 1-Apr Plant beans, squash
Crimson Clover blooming 29-Apr 2-May 16-Apr 22-Apr 23-Apr 27-Apr 18-Apr 25-Apr 4-Apr
Whippoorwill first heard 1-May 22-Apr 15-Apr 24-Apr 17-Apr 25-Apr 8-Apr 14-Apr 5-Apr
Galinsoga germinating 1-May 22-Apr 16-Apr 20-Apr 6-Apr
White Oak “squirrel’s ear” 20-Apr 26-Apr 23-Apr 26-Apr 25-Apr 14-Apr 23-Apr 12-Apr Plant sweet corn
Tulip Poplar blooming 2-May 10-May 3-May 26-Apr 3-May 6-May 26-Apr 28-Apr 17-Apr Plant sw corn 200 GDD base 50F
Ragweed germinating 20-Apr 16-Apr 25-Apr 26-Apr 21-Apr Plant sw corn 200 GDD base 50F
Last Frost 24-Apr 4-May 3-May 1-May 8-May 17-Apr 19-May 10-May 14-Apr 25-Apr Average 4/30 (10 yrs)
Fireflies 7-May 2-May 1-May
Colorado Potato Beetle adult 22-May 3-May 7-May 29-Apr 27-Apr 3-May 25-Apr 2-May
Strawberries ripe 10-May 17-May 12-May 10-May 7-May 15-May 3-May 10-May 7-May
Purslane germinating 26-May 8-May 22-May 5-May 20-May 15-May 8-May
Baby Grasshoppers 12-Jul 30-Jun 26-Jun 17-Jun 16-May
Cicada first heard/seen 14-May 5-Jul 3-Jul 29-Jun 17-May
Hardneck garlic mature 14-Jun 19-Jun 13-Jun 5-Jun 4-Jun 30-May 9-Jun 11-Jun 6-Jun 31-May
Foxgloves bloom 6-Jun 11-Jun 8-Jun Bean beetle eggs hatch
Bean Beetle eggs 4-Jun 16-Jun 10-Jun 6-Jun 20-Jun Hatch when foxgloves bloom
Japanese Beetle first seen 16-Jun 21-Apr 15-Jun 20-Jun 29-Jun 21-Jun 850 GDD (base 50F)
“June” Bugs first seen 5-Jul 11-Jul 2-Jul 12-Aug 10-Jul 30-Jun 29-Jun 30-Jun 23-Jun
Corn Earworm first seen 28-Jul 8-Jul 12-Jul 10-Jul 14-Jul 150-490 (base 54F)
Fall Dead-nettle germinating 1-Sep 20-Aug 30-Aug 20-Aug 16-Aug 20-Aug 15-Aug 29-Aug 18-Aug Plant spinach
Fall Henbit germinating 28-Aug 20-Aug 29-Aug 18-Aug
Fall Chickweed germinating 7-Sep 7-Sep 5-Sep 6-Sep Plant spinach
First Fall Frost 3-Oct 6-Nov 27-Oct 13-Oct 29-Oct 20-Oct 19-Oct 23-Oct 30-Oct 22-Oct Average 10/22 (9 yrs)
Harmonia Ladybugs migrate east 18-Oct 12-Nov 21-Oct 27-Oct
Garlic planted (hardneck) 25-Oct 20-Oct 9-Nov 3-Nov 11-Nov 1-Nov 5-Nov 11-Nov 15-Nov 6-Nov Soil temp 50 F
Event 2003 2004 2005 2006 2007 2008 2009 2010 2011 2012 2013 Notes

Crop review, harvesting roots

Large Smooth Prague Celeriac
Photo credit Southern Exposure Seed Exchange

This week in the garden we have started fall clean-up. We packed away the rowcovers preserving the last rows of green beans, squash and cucumbers, and harvested the last of those crops. Two nights with lows of 22F made it clear it was time. We removed the okra and eggplant “trees”, and pulled up the t-posts from the tomato rows and the asparagus beans. We bundled the asparagus bean trellis netting, along with the bean vines, and tied it up in the rafters of our greenhouse. It will stay there till spring when we will dance on the bundle in the parking lot and shake out the dried bits of vine, so we can use the netting for the 2013 crop.

We discovered we can use our power-washer to clean the t-posts before storing them. This saves a lot of time, and converts the job from a tedious chore with knives and wire brushes into a “power rangers” opportunity. We like to get the posts really clean before storing them to reduce the chance of carrying over soil-borne tomato diseases to next season.

White Egg turnip
Photo credit Southern Exposure Seed Exchange

We have started clearing crops which are less cold-tolerant. This week we are working on the vegetables that get killed at temperatures of 25°F and 20°F. Fall weather in our part of Virginia doesn’t usually get this cold this early, but there’s no arguing with it. We’ve got the Chinese cabbage (Napa cabbage) in and we’re going for the small bit of bulb fennel soon (both 25°F crops). We’re picking the broccoli twice a week as long as it lasts, although yields are right down now. Next we’re after the celeriac, turnips (no rutabagas this year), and winter radishes. Sadly our fall beets all failed, so we don’t need to dig those. We still have some from the spring crop in good condition in perforated plastic bags in the fridge.  Kohlrabi, cabbage, carrots and parsnips are more cold-tolerant, so they can wait to get harvested in a few weeks. We still have lettuce and celery outdoors under rowcover and hoops. And some of the greens and hardier leeks will feed us all through the winter. Twin Oaks is now in Climate Zone 7a. This means the range of the average annual minimum temperature is 0°F to 5°F.

Popping garlic cloves in preparation for planting
Photo credit Southern Exposure Seed Exhcange

We’re getting ready to plant garlic. The soil has certainly cooled down enough this year! We decided to cut back our total amount of garlic planted this year for two or three reasons. One is that we think we’ll still have enough if we plant 16% less, and maybe we’ll be less wasteful. Another is that we hope the time we’ll save at harvest and curing will enable us to take better care of what we have got, and less will get wasted that way. Another is that it will help our crop rotation in the raised beds, where we grow a lot of alliums – garlic and potato onions over the winter, onions in spring, shallots and scallions in the mix, and leeks from mid-summer to late winter. Sometimes doing a smaller amount well is more productive than over-extending ourselves  with a big crop.

Yesterday we started separating the garlic cloves (“popping” the cloves) at our annual Crop Review meeting. This is when the crew gathers to work through an alphabetical list of crops we grew and talk about what worked and what didn’t and what we want to do differently next year. We plan to try a small amount of West Indian gherkins as an alternative to pickling cucumbers, which seemed plagued by disease. (I saw some very robust gherkins growing at Monticello in September.) We’re looking for a heat-tolerant eggplant variety to trial alongside our well-liked Nadia, which shut down during the early summer heat. We intend to make smaller plantings of edamame next year, and harvest smaller amounts more often, so less goes to waste. We want to try Sugar Flash snap peas and another dwarf early-yielding type of snow peas. (Dwarf Grey works for us, but Oregon Giant didn’t). We’re going to try some purple bush beans to see if that helps us get harvests of nice small beans and fewer ugly giants in the buckets. We debated the harvest size of okra and asparagus too. We vowed to grow fewer different varieties of broccoli and try to find a decent red cabbage. This year we tried Integro, Ruby Perfection and Mammoth Red, but none produced a good amount of nice sized heads. We used to be happy with Super Red 80, but gave it up after two bad years. next year we’ll try Red Express. We strategised about to get red sweet peppers as early as possible.

As the tasks to do outdoors start to wind down, we’re upping the pace of our winter planning season. Our next tasks include doing an inventory of the seeds we still have and figuring out our garden plan, so that we can work towards ordering the seeds we want in sensible quantities.

Twin Oaks November Calendar (and December)

Garlic shoots emerging through the mulch in November

November -The End is in Sight

During the month

Lettuce Factory: Sow lettuce in hoophouse, for January transplants.

Write Thank You Letter to Paracrew (part-time workers)

Early November: Finish up sowing cover crops in Nov. Can sow winter wheat in early November (won’t winter-kill). Sow wheat or rye in carrot beds by 11/30(?), or if too late for cover crops, just spread carrot tops on beds.

Sow onions to overwinter in hoophouse.

Plant hard-neck garlic when soil temp at 4″ deep is 50°F, and mulch immediately, not too thickly.

Plant soft-neck garlic.

Plant leftover small garlic cloves for garlic scallions and garlic greens.

Potato onions: till beds.  11/1-12/1: Plant medium-size (1½-2” diameter) potato onions, at 6”, or wider if supply is limited.  Cover with ½-1” soil, then mulch. If planning a January planting of small potato onions, prep bed and roll mulch now.

Sow spinach (for spring harvesting) in early November if not done already.

Mid November: Free trapped garlic shoots from over-thick mulch, when 50% emerged.

Cover lettuce, spinach (“burns” below 10°F), celery, zukes & cukes and Chinese cabbage. Use double hoops for the spinach, celery, and the last lettuce bed.

Harvest: celeriac (hardy to 20°F), beets (15-20°F), turnips(20°F), kohlrabi (15°F), winter radish (20°F), rutabagas (OK to 20°F), carrots (12°F), parsnips (0°F) in that order. Wash and store in perforated plastic bags in walk-in cooler. Record yields.

After curing, store boxes of sweet potatoes in basement cage (55-60°F, 80-90% humidity).

Sort white potatoes in storage 2 weeks after harvest.

Spread lime or gypsum as needed, referring to soil analysis results.

Potato Onions: sell small ones (<1½”) or store on racks until January. Ideal conditions 32-40°F, 60-70% humidity, good ventilation, layers < 4” deep. Do not seem to suffer from freezing.

Winterize the rototillers and BCS mower.

Planning:

Week 1: Check the accounts and prepare Budget Requests for economic planning. Write Informant. Revise Seed Inventory spreadsheet.

Week 2: Inventory seeds

Week 3: Inventory seeds

Week 4: Seed Inventory: proof reading, etc. File notes.

Perennials: Cut dead asparagus tops with weed whackers or machetes, and remove all ferns. Weed strawberries and spread sawdust in aisles. Weed and fertilize rhubarb, blueberries, asparagus, and spread cardboard and sawdust, (hay for asparagus if possible). Weed grapes, take vine cuttings. Transplant new blueberries if needed.

November Harvests: last outdoor lettuce (hardy to 15°F with rowcover), beets (15-20°F), broccoli (25°F), cabbage (12°F), cauliflower, celeriac (20°F), celery (15°F with rowcover), chard (10°F), fall greens, collards (5°F), fennel (25°F), kale (0°F), kohlrabi (15°F), komatsuna (15°F), leeks (fall leeks hardy to 12-20°F, winter ones to 5°F or lower), parsnips (0°F), scallions (25°F), senposai (12°F), spinach (0°F), tatsoi (10°F), turnips (20°F), yukina savoy (10°F).

December – Time to Rest

Perennials: see November. Cut fall raspberry canes (after leaves have dropped) with pruners, to the ground. Weed raspberries. Hang blueberry drip tape in the branches. Dig docks from asparagus patch.

Plant medium potato onions, if not done in November.

Drain and store the hoses and irrigation. Clean up stakes, labels.

Planning:

Week 1: Prepare seed order spreadsheet. Decide seed order.

Week 2: Revise Lettuce List, lettuce Log. Spend last of money. Check expenditures and spend remaining budget. File the year’s accumulated notes.

Week 3: Put your feet up and read seed catalogs and inspiring gardening books

Week 4: Put your feet up and read seed catalogs and inspiring gardening books

December Harvests: cold frame spinach or lettuce, cabbage (hardy to12°F), celery (15°F with rowcover), chard (10°F), collards (5°F), kale (0°F), komatsuna, leeks (fall leeks hardy to 12-20°F, winter ones to 10°F or lower), parsnips (0°F), senposai (12°F), spinach (0°F), yukina savoy (10°F).

Winter Squash in storage at Twin Oaks potato onion planting, potato onion storage,

Home from CFSA, Superstorm Sandy

Beauregard sweet potato
Photo Southern Exposure Seed Exchange

Superstorm Sandy didn’t do us much damage, luckily. It’s been raining for 40 hours, but we’ve only got 2.8 inches so far and it looks like it’s going to clear up later today. Despite my worries about the broken hoophouse windows blowing in and us losing our newly re-plasticked hoophouse, it didn’t happen. We didn’t have any really high winds, and we didn’t even lose power, but of course we did all the prep work.

Georgia Jet
Photo Southern Exposure Seed Exchange

Yesterday we re-stacked our sweet potatoes which had finished curing (the skins don’t rub off any more). We moved them into a wire rodent-proof cage, and close-stacked them, taking away all the sticks that spaced the boxes during curing. I haven’t got numbers for the total yield yet, but it comes to 96 boxes. The Georgia Jet produced 42 boxes and the Beauregard only 32 from the same length row. Our two heirloom varieties produced three boxes each. We don’t expect many of them, but we are keeping the varieties alive, because genetic diversity is important and who knows what secret virtues these varieties have?

We also bravely spent time in the rain, digging drainage ditches to reduce the impact of the hurricane. They seem to have worked quite well. And we draped the soggy rowcovers over the frost tender crops, in anticipation of freezing conditions.

While I was away at the CFSA Conference, the crew harvested the white potatoes. We got a good yield (also no numbers yet), but we got a disappointingly large number of greened potatoes. (Green from being exposed to the light.) I think the reason is that our new experimental tractor-mounted furrow-making disks don’t make furrows as deep as we need. The walk-behind BCS furrower on the rototiller made adequate furrows, but not as good as the old Troybilt furrower. This flags a need to research better gear before March.

I had a great time at the CFSA Conference. I think there were about 700 people there. About 70 came to my workshop Growing Great Garlic, on Saturday afternoon. They were very appreciative, and I managed OK without my notes! It’s not as bad as it sounds – I had a slideshow and had practiced quite a few times, and knew it better than I would have guessed. Somehow I couldn’t get my notes on the laptop screen without them also appearing on the big screen along with lots of clutter. This flags a need to find out before my three workshops at the Southern Sustainable Agriculture Working Group conference in Little Rock, Arkansas, January 23-26. Busy, busy.

The conference was very well organized and the food was spectacular – mostly local and sustainably grown. I had the chance to attend several workshops by other people. Tony Keinath, the vegetable pathologist at Clemson University, talked on Sustainable and Organic Approaches to Managing Cucurbit and Tomato Diseases – a very well-prepared and information-packed session. I feel in a better place to tackle next year’s plagues now. I was struck by the fact that he had seen NO benefits of using Oxidate, the hydrogen peroxide disease control product.

A workshop I found particularly valuable was Laura Lengnick‘s presentation “Is Your Farm Climate Ready?”  She is doing valuable work to help farmers get ready for climate variability. She is one of the main authors of a USDA ARS report Climate Change and Agriculture: Effect and Adaptation. Its publication date is November 14 2012. She also spoke at the August 2012 symposium of the Ecological Society of America, Climate change impacts on agricultural systems:

She suggests viewing climate change as yet another production risk to assess and prepare for. The vulnerability of your farm has two components: exposure and adaptive capacity. As far as vulnerability, the most immediate key exposure is water issues (too much and too little). Rising air temperatures, including night temperatures, more extreme temperatures provide threats and some opportunities. Increasing CO2 levels will provide some positive effects such as faster crop growth. As far as adaptive capacity, the main feature of that aspect is our personal capacity to respond and plan. Laura Lengnick says “Greater attention to climate as critical for decision-making is expected by future generations of producers.” We need to start with ourselves.

Baby ginger, ready to be eaten, pickled, candied, frozen.
Photo East Branch Ginger

Next I attended a workshop by Susan Anderson of East Branch Ginger, and learned so much about how to do the best by this crop, that I am looking forward to an even bigger harvest next year. This year we harvested 165 pounds, and saved 65 pounds as seed stock, so we can plant a bigger patch in next year’s hoophouse.

Harvested baby ginger, about 6 months old
Photo East Branch Ginger

Meanwhile I’ve finished my next article for Growing for Market. My working title is Knowing When to Take Action. It’s the third part of my series on being a resilient farmer. This article includes scouting and monitoring for pests and diseases; using pest and disease forecast services; and being prepared for the effects of extreme high and low temperatures. When is it time to cut your losses? A big part of the article is a table of soil temperatures to help when deciding planting and harvesting dates.

Sweet potato harvest – all in!

Our sweet potato harvest well underway.
Photo credit Wren Vile

           

Usually sweet potatoes are harvested the week the first frost typically occurs. In anticipation of frosts (that didn’t happen) on Sunday and Monday nights, we harvested this week. Contrary to myth, there is no toxin that moves from frozen leaves down into the roots. On the other hand, cold injury can ruin the crop, and roots without leaf cover are exposed to cold air temperatures, and have lost their method of pulling water up out of the soil. Cold wet soil can quickly rot sweet potatoes (I know, it’s happened here).

To harvest, we first remove the vines from the area to be harvested that day. There is usually 3 afternoons’ digging for ours, and we want to leave live vines to protect the rest of the crop overnight. We use pruners to snip the vines where they emerge from the soil, leaving stumps to show where to dig. We roll the vines into the spaces between the rows.           Using digging forks, we carefully dig up the roots, which grow in the ground in a bunch-of-bananas shape. We want to select good potatoes for seed, and we grow several different kinds (Georgia Jet, Beauregard, and a couple of heritage varieties whose names we don’t know), so we make sure not to mix potatoes from different rows. As we dig, we set the potatoes out beside the spot where they’ve grown, one clump per plant, so it’s easy to identify the most productive plants.

It’s important not to bruise the roots, or to leave them exposed to temperatures higher than 90°F (32°C) for more than half an hour, or they will get sun-scald. Below 55°F (13°C), they’ll get chilling injury. We also avoid any abrasion of the skin, which is very fragile at this stage. We leave the sweet potatoes to dry on the ground for 1-2 hours, unless the weather is unsuitable. This year we had ideal weather, not too hot, not too cold; breezy enough to dry the skins, sunny.

We want to grow our own slips (baby plants) next year, so we save at least 1 root per 5 slips wanted.  (1 good slip every 16″.) So to plant 800 row feet, (600 slips), we save 100 each of our two main varieties and 20 each of the two heirlooms. That should be plenty. Some will shrivel or rot, so we allow a margin. We don’t save for seed any roots that look diseased. We choose plants with a high yield and no string (rat-tail) roots. From these plants, we choose small-medium sized potatoes with typical shape and color.

When grading and crating the roots in the field, we first choose the seed potatoes, and then sort storable from “Use First” roots. Large open broken surfaces will cure and can be stored, but any roots with soft wet damaged areas or deep holes (whether from voles, bugs or fork tines) will not store, and should be graded out, for composting or immediate use. We sort into 4″ deep wood flats or 5″ plastic crates for curing, and buckets for the “Use First” category.

Immediately after harvest, we took the boxes of sweet potatoes into a warm damp basement below the dining hall, to cure. This allows the skin to thicken, cuts to heal over and some of the starches to convert to sugars. Uncured “green” sweet potatoes are not very sweet at all, and are better used in dishes where they combine with other foods. A baked uncured sweet potato is a sad disappointment.

We stack our boxes of roots on pallets, and put wooden spacer sticks between boxes in each stack, to ensure air flow. We get quite good temperatures, but keeping humidity up is difficult for us. We cover the flats with newspaper to hold in some moisture. The best result seems to come from splashing water on the concrete floor several times each day. We use box fans to improve the airflow, and the basement already has some natural ventilation.

Ideal conditions for curing are 85-90°F (29-32°C), and 80-95% humidity for 4-7 days, with some airflow and ventilation. Curing takes longer if conditions are less then perfect. The length of the curing period also varies with the dryness of the soil just prior to harvest. We usually reckon on 10-14 days. During that time, we’ll be taking turns to stoke the stove in the basement to keep the temperature up.

So – how did we do this year? Middle of the road, I’d say. Decent yields, but not a bumper crop – we still had empty boxes left over. The deer were regularly eating our vines until quite recently. Last year we had a dog to chase the deer off, but he met with a road accident. His replacement was old, and she just wanted to be a pet, so we had deer again. We used drip irrigation and biodegradable plastic mulch this year, and did a good job of weeding, so I put the lower yields down to deer damage.

Last year’s (weedier!) sweet potato field.
Photo credit Kathryn Simmons

Now the harvest is complete, we will disk the area and sow cover crops. It’s too late in the year for oats. We can sow wheat, winter rye and Austrian winter peas up till 10/31. We prefer winter wheat after the sweet potatoes,  because we’ll use that area next year for spring white potatoes in mid-March, and rye takes too long to break down early in the spring.

Twin Oaks October Calendar (Slowing Down)

Morris Heading Collards – our favorite
Photo credit Kathryn Simmons

Here’s our list of tasks for October. If you garden in zone 6 or 7, your list might be similar. If you live in a very different climate zone, leave a comment about your list for October, and how many weeks different your area is from ours.

During the month

Weed and thin fall crops in raised beds, especially spinach and kale. Thin carrots to 3”, kale to 12”.

Lettuce Factory: Transplant sowing #37 to fill cold frames; #38, 39, 40, 41, 42 in Greenhouse beds (9″ spacing).

Frost Alert:

Watch the forecast and if frost is expected that night

When frost threatens, harvest all peppers exposed to the sky. Corona is one of our favorite orange peppers. Photo credit Kathryn Simmons

Harvest peppers facing the sky, tomatoes, cauliflowers, corn, cowpeas, limas, eggplant, melons, cukes, okra, winter squash, Blues cabbage (hardy to 25°F), if not already done.

Double hoop and cover: lettuce, celery (hardy to 16°F with row cover).

Spring hoop and cover: squash, cucumbers.

Cover celery to extend the harvest into mid-winter. We like Ventura.
Photo credit Kathryn Simmons

Rowcover (no hoops): beans, Chinese cabbage, pak choy, Tokyo bekana, seedlings for hoophouse, collards  (hardy to 10°F, but cover keeps quality).

Cold frames:  Row cover between 32-28°F.  Add lids between 28-15°F.  Add quilts below 15°F.

Foliar spray greens with seaweed a few days before frost, to toughen them up.

Use overhead irrigation on peppers & tomatoes at night and some raised beds with tender crops.

Early Oct: Finish sowing spinach, kale by 7th for overwintering (last chance).

Transplant lettuce #37 to fill cold frames; #38, 39 in Greenhouse (9″ spacing).

Roll up drip tape from winter squash and sweet potatoes.

It’s time to roll up the drip tape from the watermelon, winter squash and sweet potato patches, in preparation for disking and sowing winter cover crops.
Photo credit Kathryn Simmons

Move stored garlic from basement to fridge – store below 40°F or above 56°F, never 40-50°F.

Mid Oct: Till finished raised beds and sow wheat or rye before the end of the month.

Garlic Beds: Compost (5-6 tractor buckets), till and prepare beds.

Transplant lettuce #40, 41, 42, 43 in Greenhouse as needed, filling any gaps.

Get soil tests done, when soil is not too wet.

5th fall disking: By mid-month disk and sow cover crops where possible. Sow wheat or rye as covercrops – too late for oats or most clovers (Austrian Winter Peas Sept 15-Oct 24).  Could sow winter wheat mid-Sept to early Nov (good for small plots that are hard to reach with the tractor) and after sweet potatoes).

Harvest peanuts mid-late Oct after a light frost.  Wash, dry, cure 6 days in solar dryer facing east (don’t heat over 85°F), store.

A well-covered sweet potato patch.
Photo credit Kathryn Simmons

Harvest sweet potatoes before soil temps go much below 55°F, or night air goes below 50°F: on 3 mild days – generally in the week that first frost usually occurs (10/7-14). Even a few hours exposed to temps below 50°F will cause chilling injury. (Frost on the leaves does not of itself damage the roots). Clip vines, dig carefully, set tubers in plant-clusters to dry on the soil. Select seed tubers (med-size tubers from high-yielding plants).  Save 100 Georgia Jet, 100 Beauregard, 20 each White and Jubilee. Cure in boxes with wood spacers and cover with newspaper, in basement with furnace going full time, for 7-10 days (85-90°F, 80-90% humidity).  Use fans. Splash water on floor. Curing is complete when skin is undamaged after rubbing two together. Restack boxes in storage cage.

Harvest white potatoes before the first frost (average Oct 14) if possible. Cure in root cellar at 60-75°F for 2 weeks, with good ventilation, then cool the cellar to lower temperatures: 50°F by 10/31, then 40°F for the winter.

Late Oct: Transplant lettuce #44, 45, 46 as filler in Greenhouse. Double hoop and cover spinach.

Planning: List successes & failures from labels. Prepare Garden Planning Schedule, Crop Review Sheets. Clean labels after info is recorded. Pray for a killing frost. File crop record info. Audit labor budget and plan endgame. Plan main garden layout. Hold Crop Review meeting.

Clear winter squash, tomatoes and peppers in order to sow cover crops, by 10/24 if possible. Sow rye alone or with crimson clover or winter peas. Crimson clover by 10/14; AWP, wheat by 11/8

6th fall disking: After the killing frost, or end of Oct if no frost: pull up tomato stakes and roll up drip tape, disk nightshades, melons, winter squash, sweet potato and white potato patches.

Check through veg in storage, squash once a week, white potatoes two weeks after harvest.

Perennials:Last mowing of clover in grapes in early Oct, not too short, and not too late in the year. Weed & mulch strawberry beds, and remove extra runners. Renovate if not already done. Start weeding, fertilizing and mulching the blueberries, raspberries, rhubarb and grapes.

Time to say goodbye to the rhubarb until April.
Photo credit Kathryn Simmons

October Harvests: Asparagus beans, beans, beets and beet greens, broccoli, cabbage, cantaloupes, carrots, cauliflower, celeriac, celery, chard, Chinese cabbage, collards, corn, cow peas, cukes, edamame, eggplant, horseradish, hot peppers, kohlrabi, komatsuna, leeks, lettuce, limas, maruba santoh, okra, pak choy, peppers, radishes, Roma paste tomatoes, scallions, senposai, spinach, tatsoi, tokyo bekana, tomatoes, turnips and turnip greens, winter radishes, winter squash, yukina savoy, zucchini.  Could lightly harvest rhubarb before frost.

Article on resilience in the September Growing for Market magazine

September 2012 issue of Growing for Market

The September issue of Growing for Market magazine is out, and with it, my article Building resilience into farm systems. I’ve embarked on a four-part fall and winter series of articles aimed at helping growers thrive under varying situations, some of which we have no control over.

This first article is about being prepared for whatever Nature throws at you, expecting to adapt, and building in options. I’ve sent in the second article, about  understanding and predicting conditions,for the October issue. It covers weather forecasting, frost prediction, Growing Degree Days and phenology. The next one after that will include using soil temperatures, scouting and monitoring for problems and something about on-the-spot decision-making. The last one will deal more with decision-making, reviewing results and learning from mistakes.

To read the articles, get a subscription to the magazine.

How Buildings Learn, by Stewart Brand

For those who like inspiring background reading, I recommend Stewart Brand in How  Buildings Learn: What Happens After They’re Built (Penguin 1995). He advocates for
constructing buildings that are easy to modify later, in gradual or drastic ways to meet the changing needs of the people inside. Farms can be looked at similarly. Keep as many options as possible (for crops, cover crops, crop layout) open for as long as possible. Brand’s current main activity is through The Long Now Foundation

The Art of the Long View, by Peter Schwartz

It can be helpful to do some scenario planning, which I learned about when I read The Art of the Long View, by Peter Schwartz (Doubleday, 1991). Scenario Planning is a method of making flexible long-term plans, using stories (scenarios) to help us visualize different possible futures that include not only factors we don’t control, like the weather or the market’s enthusiasm for bulb fennel, but also intangibles such as our hopes and fears, beliefs and dreams.

No time to read books? Very sad! Maybe see you at the Heritage Harvest Festival at Monticello, near Charlottesville, this Friday and Saturday.

Last Chance Sowings

This week we’ve been busy tilling and raking beds in preparation for some Last Chance sowings.

In our climate zone, with an average first frost date of October 14, the first half of August is the last chance to sow several vegetables and get crops from them before winter. It’s important to know the last date for planting each crop so that you have a reasonable chance of success. For this part we got help from the Virginia Tech Extension Service: Fall Vegetable Gardening. 

The first group of Last Chance sowings are the warm weather crops, such as green beans, cucumbers, zucchini and summer squash.

Here’s the formula (for frost tender crops), for figuring the number of days to count back from the expected first frost date; add the number of days from seeding to harvest, the average length of the harvest period, 14 days to allow for the slowing rate of growth in the fall, and 14 days to allow for an early frost. For example, yellow squash takes maybe 50 days from sowing to harvest, and the plants are good here for 21 days, so the last date for sowing would be 50+21+14+14= 99 days before the first frost. For us that means 99 days before 10/14, so 7/7. But with rowcover to throw over the last planting when it gets cold, the growing doesn’t slow down, and the season is effectively 2 weeks longer, and we can ignore the 14 days for an early frost. So our last planting of squash is 8/5, a whole month later than if we didn’t use rowcover..

But August is way to soon to be thinking about frosty weather, except to ensure we have enough rowcover on hand when the time comes. Here, and in many parts of the country, a frost or two will often be followed by a few more weeks of warm weather, so getting past the first few frosts is the effort. It’s easy to get extra harvests for a month or two from mature plants you already have.

We sow our #6 planting of beans 8/3, 15 days after #5; cukes #5 (slicing), by 8/5 at the latest; and zucchini and summer squash #5 by 8/9.

The second group of Last Chance sowings are cool weather crops that grow here in spring and fall, but don’t thrive in the summer. Beets, carrots, chard, turnips and radishes all fall in this group. It can be hard to get some of these to germinate when the soil is still hot.

On 8/1 we sow beets dry or presoaked for 2-12 hours in a little water – not too much water or for too long, as they need to breather air, or could drown. We sow them 1/2″-1″ deep, tamp the soil, and keep the surface damp with daily watering for the 5 or 6 days they take to emerge. We have tried using shadecloth to help keep the soil moist, but it does cut down the airflow and our climate is humid and fungus-inducing. I like the Formanova/Cylindra/Forono beet. The shape is long (good for slicing), and the flavor is very sweet and the texture tender.

Very early in August, or sometimes in late July, we sow a large planting of fall carrots, enough to store and feed us all winter. Danvers 126 is our workhorse carrot. We use an EarthWay seeder, which is light, easy to use and to empty, and comes at a reasonable price. There are more expensive precision seeders that put the seed out more evenly, and so don’t require the amount of thinning that using the EarthWay does, but we’re happy with our choice. We use pre-emergent flame weeding to remove the first flush of weeds, making it easy to then hoe between the rows.

Carrots and beets are ideal crops for this technique. The goal is to flame the bed the day before the expected emergence of the crop. use a soil thermometer and a table of how many days the crop needs to germinate at various soil temperatures, to figure out which day to flame. For carrots it’s possible to sow a few “indicator beets” at one end of the bed, and as soon as you see the red loops of the beet seedlings breaking the surface, flame the carrots. (But look for carrots too, just in case!) Beets are always a bit quicker than carrots to germinate. Tables of Days to Germination can be found in Knott’s Vegetable Growers’ Handbook (Wiley, 2006), by Donald Maynard and George Hochmuth, and Nancy Bubel’s New Seed Starter’s Handbook. (Rodale, 1988)

We use a handheld flamer attached to a propane cylinder that is in a wheelbarrow pushed by a second person behind the first. this person also acts as a “fire warden”. Some growers mount the propane on a backpack frame. Walking along the aisle between the beds, and wafting the wand diagonally back and forth across the bed takes about 10 minutes for a 100′ (30 m) bed. Flame weeding alone can reduce the hand weeding to one hour/100′. Hand weeding can be reduced to 6 minutes/100′ by flaming after using stale beds which have been hoed 3 or 4 times.

Swiss Chard can also be sowed here in August, for a nice fall harvest. We sow ours in April and just keep it going all summer, fall and (if covered) winter too.

At the beginning of August we sow winter storing radishes, China Rose, Red Meat, Shindin Risoh Daikon and Shunkyo Semi-Long. We also sow Easter Egg small radishes. We can have trouble with flea beetles as well as harlequin bugs on our fall brassica sowings, as the pest numbers have built up over the summer. To avoid these troubles, we put rowcover over the beds until the plants are big enough to stand up for themselves against “pest bullying”.

We sow 6 beds of kale, two each every 6 days, (8/4, 8/10, 8/16, 8/24) until we succeed in getting enough established. Often we’ll get patchy emergence and end up transplanting plants from one bed or one end of a bed to fill out the blank areas.

We sow our turnips 8/15 or up until 9/15 (our absolute latest). Rutabagas need longer than turnips, and we’ve given up growing them because late July weather is just too hot and dry. Brassicas will germinate just fine in hot temperatures – the challenge is keeping the soil moist.

Potato Planting and Carol Deppe’s Writing

A ladybug on a potato leaf, looking for pests

We’ve just planted our second crop of potatoes for the year. At 3450 row ft (about a quarter of an acre), this planting is a bit bigger than our March planting. We aim to grow a whole year’s worth of potatoes for a hundred people. Planting in June has several advantages – for us the main one is that we can store this harvest in a root cellar over the winter, without using any electricity to control temperature. If we planted our whole year’s supply in March, we’d harvest in July and have to store them over the summer, and then all the way round till the next July. It’s also nice to split the work up into smaller chunks.

Up until this spring, we made furrows for our potatoes and covered and hilled them using a BCS 732 rototiller (or walk-behind tractor, as the retailers prefer to designate it). This is doable, but labor-intensive. This year we set up a toolbar on the tractor with sweeps to make furrows, and then discs to form hills. It’s been a learning process, with some teething troubles, but  I do think it’s the way of the future for us. (I just don’t have the stamina for all the rototilling any more!).

Compared to using the rototiller, the tractor needs a lot more space to manoeuver. We were lucky in having an area of cover crops next to the potatoes for this planting, so we could run over the edge onto “next door”. In the spring planting, we had a hydrant in the middle of the patch. that’s a minor problem with the rototiller, but a bigger problem with the tractor. Keeping the row spacing tight is harder with the tractor, and in the spring, we ended up with some wider spacings, which lead to more weeds than usual, and poorer hills. This week (our second time using the tractor), we managed much better row spacing. Next year, we’ll allow more space to turn the tractor, right from the planning stage.

Another “surprise feature” this time, was that it rained right after we’d planted (yes, before we’d covered the potatoes). The forecast had suggested a small chance of showers later in the day, but the 3/4″ drenching was a complete surprise! So we had to wait two days for the soil to dry out enough to take the tractor again. The soil was clumpy, but not impossible. Probably we could have covered and hilled sooner with the rototiller, as it weights less, and compacts the soil less. And the soil would have ended up with a finer texture. Overall I think the trade-offfs of using the tractor are worth it.

The potatoes came to no visible harm sitting in their furrow for two days. We had pre-sprouted them, so the sprouts grew a bit bigger and greener. Luckily we didn’t have extremely hot temperatures those days.

Recently I learned some new information about ideal soil temperatures for potato planting. This came from a workshop on Sustainable Potato Production by Rusty Nuffer at Southern SAWG in January 2012. In spring, wait for soil temperatures to reach 50F (10C) before planting. In summer, the ideal soil temperature is 60-75F (15-24C). Ours was 70F (21C). It’s possible to pre-irrigate to lower the soil temperature in summer. (And hopefully nature won’t mid-irrigate for you as it did for us this week!)

 Carol Deppe, author of the wonderful book The Resilient Gardener: Food Production And Self-Reliance In Uncertain Times, has written a very interesting article The 20 Potato a Day Diet versus the Nearly All Potato Winter about the nutritional and gastronomic wonders of potatoes.  It will inspire you to grow and eat more potatoes!