Sweet potato harvest and eggplant varieties.

Bountiful sweet potato harvest Credit Twin Oaks Community

Bountiful sweet potato harvest
Credit Nina Gentle

Our sweet potato harvest is huge this year! We mostly managed to keep the deer out of the plot, by luck and a scarecrow and things that fluttered in the breeze. We’ve filled all our usual boxes and then scrambled twice to find more! There are about 20 plants we didn’t have time to dig up yesterday (our fourth harvest day). Hopefully we’ll get those out of the ground before the rain moves in. A big storm system is approaching from the south west. We’ve been lucky that we haven’t had any very cold weather since that first light frost on 10/5. I remember one awful year when we left the sweet potatoes in the ground too late, hoping they’d fatten up a bit to make up for a poor growing season. Instead, the weather got cold and wet, and the sweet potatoes were rotting in the ground (it was November by then), and those that didn’t rot got chilling damage that prevented them ever softening in cooking. Sweet potatoes that stay hard are no fun to eat! I wrote the harvesting details in an earlier post.

Boxes of sweet potatoes curing in our basement. Credit Twin Oaks Community

Boxes of Beauregard sweet potatoes curing in our basement.
Credit Nina Gentle

Anyway, back to this year’s good news – I counted the equivalent of 273 normal-sized boxes in the basement this morning. At 23 pounds for our standard box, that’s about 6280 pounds. We might be up to 6500 pounds by the time we’re done. This will be our record! I think our local food pantry will be getting some sweet potatoes this winter and next spring!

Last year I compared sweet potato yields for different years. We usually have about 600 plants in 800 row feet (16″ spacing). Yield is about 11 pounds/sweet potato plant this year. But as they say “your results may vary.”  Ours certainly have. Working back from 2012, we harvested 4070 lbs, 2208 lbs, 1860 lbs, “lots” (poor record-keeping!), 5590 lbs, 3820 lbs and 4050 lbs in 2007.


Nadia eggplant. Photo credit Kathryn Simmons

Nadia eggplant.
Photo credit Kathryn Simmons

This year we did variety trials of four eggplant varieties, to find one better than Nadia, which is a lovely variety, but didn’t do so well in the hot summer of 2012. Last year we ran the trial and we didn’t get a hot summer. So we tried again. Again, no hot summer! But we did good record-keeping! Here’s our table for this year:

Eggplant Harvest 2

What can we conclude? All four varieties have similar-sized fruit. We deliberately chose purple-black tear-drop shaped eggplant because that’s what our cooks want. We didn’t include any green, striped, long skinny, orange, fluted or other unusual kinds. No judgment about people who like those!

Traviata eggplant from Osborne Seeds

Traviata eggplant from Osborne Seeds

The four varieties, Nadia, Epic, Traviata and Florida Highbush (the only open-pollinated eggplant we included) all have similar-sized fruit, about 0.6 lbs each. Nadia yielded best per plant, at 13.4 fruits over the season. Epic was next at 12.5 fruits, then Traviata with 11.7 fruits. Any statisticians reading this? Are these numbers significantly different?

 

Florida Highbush eggplant from Seed Savers Exchange

Florida Highbush eggplant from Seed Savers Exchange

Florida Highbush was a poor fourth with an average of only 6.8 fruits per plant. Maybe we’ll drop that one from our experiments. On the other hand, with a name like that, perhaps it would do better than the others in a really hot summer!

Nadia eggplant from Johnnys Seeds

Nadia eggplant from Johnnys Seeds

The records are also helpful in seeing the flow of the harvest. We started harvesting 7/7. Nadia wasn’t ready. They peaked 8/6. We peaked 9/27 (“Almost over”!), after doing a drastic over-harvesting 9/24. We’re farmers not scientists!

 

 

 

Epic eggplant from Osborne Seeds

Epic eggplant from Osborne Seeds

On that theme, notice that one bed had thicker rowcover than the other, when transplanted. The two beds were next to each other. One was all Nadia, the other, the three contenders. The row cover could have skewed the results. Onward and upward! Maybe next year we’ll get some results we can bank on.

Sweet potatoes, statistics and inspiration

A bumper crop of sweet potatoes. Credit McCune Porter

A bumper crop of sweet potatoes.
Credit McCune Porter

After a week of drizzle, it finally eased up and we started harvesting our sweet potatoes. I wrote a lot about this topic last year, so I won’t go into many details here. As usual, we set the dug roots in clusters, so we could see which plants yielded most and chose medium-sized roots from those to grow our slips next year. In the picture above, we are crating the sweet potatoes after someone has gone through selecting the seed roots. In the right background you can see our grid-linked solar array. In the left background is our hoophouse, and to the left is our dying last sweet corn planting. We have one last picking today, from the Silver Queen at the far end. We used a low electric fence around this patch to keep the raccoons out, and either it worked, or the beasts didn’t notice this planting. We didn’t get any visits from tigers or elephants either! Also visible in the photo above are remaining bits of the bioplastic biodegradable mulch we used. It’s made from non-GMO corn, and is great for warm-weather loving vining crops.

Not everyone likes jumbo sweet potatoes, but for those cooking for a hundred, they

Not everyone likes jumbo sweet potatoes, but for those cooking for a hundred, they save a lot of time. Credit McCune Porter

This year, the Georgia Jet seem more productive than the Beauregard – I think that’s usual. We dug about a third of the crop the first day and got 86 boxes. The second day we had a lot of other harvesting (beans and broccoli being the most time-consuming), so we only dug another 36 boxes. We’re still only 45% of the way down the patch, so we could end up with 250 or more boxes. Probably the yield will taper off closer to the end of the field as the deer were browsing on the vines all summer.

Friday update: Well, we finished harvesting yesterday, and the yield dropped off a lot where the deer had been browsing (memo: fence out the deer in future!) We got a total of 177 boxes of various sizes, perhaps about 3939 pounds, almost two tons. That’s not a record-breaker, but is second best in the past ten years.

Our yearly harvest of sweet potatoes has varied a lot, from 31 boxes (a sad year) to 243 in 2009. An average over ten years of 112 boxes, each weighing perhaps 23 pounds. We grow about 800 row feet. We always hope to have enough to last till the beginning of May, when people start to lose interest in sweet potatoes, and start hoping for tomatoes.

Now I’ve glided smoothly into the statistics section of this post, so I’ll tell you some figures for my book sales while I’m at it. New Society has sold 3320 to mid-September, from a 5000 print run. They say the book is selling well, not many returns. At Twin Oaks we’ve sold 150 of the 250 we bought in February when it came out. I’ve just set up an Author Page at Amazon, so I can tell you they have sold 940 print copies up till 10/6. They also provide me with ranking info (this could get addictive if I let it!) and my book was #40,116 when I looked. That sounds pathetic till you realize that’s out of 8 million titles. Anyway, enough vanity! As far as its usefulness to readers, having an Author Page means that if you go to Amazon, to my book page, and then click on my name, you can read my bio, and see my upcoming events, and get back to this blog.

Getting perspective on the bookselling world, I was encouraged to learn that there is being a resurgence of small booksellers, despite the Big Online One. Here’s a link to the story in the Christian Science Monitor in March this year. I learned about it from Wendy Welch of the Little Bookstore at Big Stone Gap, who I met at the Festival of the Book in Charlottesville. She has written a memoir about her bookstore, called The Little Bookstore of Big Stone Gap, which you can buy via her website, or, I’m sure, at her store.

And now on to this Inspiring story: At the Mother Earth News Fair I met a young woman of 12 who had borrowed my book from her library. She got inspired and decided to start market gardening. She succeeded in clearing $6000 in her first year, when she was 11!

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.