Preparing to order seeds

Preparing to order seeds: 6 steps + 3 extra tips

Leeks grow slowly. Sow in March to have seedlings this size in May. Order seed soon! Photo Pam Dawling

There are lots of new gardeners now, as a result of the pandemic causing people to stay at home, cook more and want more food security without going inside grocery stores. Maybe last year you bought packets of seeds in a hurry, either online or off a rack in as store. Maybe you hope your garden will go more smoothly this year and I’m here with this blog post to help you.

Or perhaps you are a new professional grower, seeking to improve your game. Or an established one, looking to hang in there by farming smarter in these hard times.

‘Tis the season for garden planning. Inventory your seeds left from last year, peruse the catalogs and prepare your seed orders. The earlier you get them in, the more likely you are to get the varieties you want, before anything is sold out. Be prepared, note your second choice, and fend off disappointment!

Vates kale seedlings for bare-root transplanting.
Photo Pam Dawling

I have a course on garden planning for home gardeners, on the Mother Earth Fair Online. It consists of eight half-hour workshops, covering all aspects of garden planning from clarifying your goals, choosing crops, making maps of what will go where, planning when you want to harvest, determining how long your rows will be and how much seed to order, deciding when to plant and scheduling everything to make the year go smoothly. There are also workshops on ways to pack more in, and how to be prepared for things that don’t go according to plan!

Mother Earth News Fair

Commercial growers and energetic home growers will also be interested in the information on garden planning in my book Sustainable Market Farming.

I have a couple of slideshows on SlideShare.net,

See Crop Planning for Sustainable Vegetable Production 2019 Pam Dawling

To view it full screen, click the diagonal arrow in the lower right.

For long-term soil health and sustainability, think about crop rotations. See Crop rotations for vegetables and cover crops 2014, Pam Dawling

Buckwheat seedlings. Buckwheat is our quickest easiest summer cover crop.
Photo Pam Dawling

 First, a basic 6 steps of garden planning

  1. See How to Decide Which Crops to Grow.

Think about what you grew last year, and whether you want the same again. Think about what you wished you’d grown. Every year we try to introduce a new crop or two, on a small scale, to see if we can add it to our “portfolio.” Some-times we can successfully grow a crop that is said not to thrive in our climate. (Brussels sprouts really don’t). We like to find the varieties of each crop that do best for our conditions. Later we check how the new varieties do compared with our old varieties. We use heirloom varieties if they do well, hybrids if they are what works best for us. We don’t use treated seeds or GMOs, because of the wide damage we believe they do. For ideas of what you might grow, see our Twin Oaks Harvest Calendar by Crop.

Sowing Rainbow Chard. in a Winstrip tray
Photo Pam Dawling

2. Are any of your leftover seeds OK to keep?

See making an inventory, and Ordering seeds! Seed Viability Many seed catalogs include information about seed longevity, and so does Nancy Bubel in The Seed Starters Handbook. Frank Tozer in The Organic Gardeners Handbook has a table including minimum, average, and maximum.

Seeds stored in glass jars
Photo courtesy of Monticello

A simplified version of how long to keep seeds is as follows:

  • Year of purchase only: Parsnips, Parsley, Salsify, and the rarer Sea Kale, Scorzonera
  • 2 years: Corn, Beans and Peas of all kinds, Chives, Dandelion, Martynia, Okra, Onions,
  • 3 years: Asparagus, Carrots, Leeks, Rutabagas, Turnips,
  • 4 years: Artichokes, Basil, Cardoons, Chard, Peppers, Pumpkins, Spinach, Squash, and Watermelons,
  • 5 years: Beets, most Brassicas, Celery, Celeriac, Chicory, Cucumbers, Eggplant, Endive, Lettuce, Muskmelons, Tomatoes,

Rather than deteriorating with age, some very fresh seed has a dormancy that needs to be overcome by chilling (lettuce).

The fuller story is that storage conditions make a big difference. Keep seed cool, dark, dry in airtight, mouseproof containers.

An old hand-drawn map of one of our garden areas.
Image Pam Dawling
  1. How Much of What to Grow?

Make a rough map of your garden space and see what will fit. Remember you can plant a later crop in the same space after an earlier one finishes. See below for more info on quantities of potatoes and garlic, two staples.

  • How Much Garlic to Plant

A yield ratio of 1:6 or 7 seems typical, and makes complete sense when you consider you are planting one clove to get a bulb of 6–7 cloves. Divide the amount you intend to produce by six to figure out how much to plant. For large areas 750–1,000 lbs/ac (842–1,122 kg/ha) are needed for plantings in double rows, 3″–4″ in-row (7.5–10 cm), beds 39″ (1 m) apart. For single rows, 8 lbs (3.6 kg) of hardneck or 4 lbs (1.8 kg) of softneck plants about 100′ (30 m). In the US, one person eats 3–9 lbs (1.4–4.2 kg) per year.

Music hardneck garlic.
Photo Southern Exposure Seed Exchange
A row of potato seed pieces ready to cover.
Photo by Wren Vile
  1. How Much Seed to Order?

Hopefully you kept some kind of record on whether the amount you bought last year was enough. When we figure out how much seed to order we add in some extra for some things – crops that can be difficult to germinate, or we really don’t want to cut too close. We add 20 percent extra for most crops, but only 5 percent for kale, 10 percent for onions and collards and 30 percent for melons. These numbers are based on our experience – yours might be different. We also know which seed we can buy in bulk and use over several years. This gives us an additional security against poor germination, or plagues of grasshoppers or caterpillars. For me, a big bag of broccoli seed for each of our main varieties gives some kind of warm glow of horticultural security! Buying too much either leads to wasting money (if we throw it away) or wasting time and money (if we sow old seed that doesn’t come up well, then have a crop failure).

If you use spreadsheets, see my post Cooking Greens in December Special Topic: Ordering Seeds.

Here’s a helpful table of 1000 Seed Weight for 13 crops. Another of the challenges with seed ordering is converting between grams, ounces and seed counts – have your calculator at the ready, or easier still, just type “Convert ½ oz to grams”into your search engine.

 

  1. Choosing varieties.

See How to read seed catalogs for tips on getting what you really want by paying attention to what’s in the small print and what isn’t mentioned. We carefully look for varieties that offer the flavor, productivity and disease resistance we need. The catalogs are starting to appear in my mail box. The early bird catches the preferred varieties! The main companies we order from are Fedco Seeds, Johnny’s Selected Seeds and of course, Southern Exposure Seed Exchange. We like SESE for regionally adapted varieties, Fedco for great prices on bulk sizes, and Johnny’s for some varieties we really like that aren’t available from the other two.

 

  1. Formatting and placing seed orders

We grow lots of different crops, so we make a spreadsheet, and include columns for the name of the supplier we buy each variety from (we just use the initial), the item number in the catalog, the packet size and the price. (Be careful though, if you carry this information over from year to year – prices change.) Once we have composed our total seed order, we sort the orders by the name of the supplier. Then we can calculate the total price for each supplier. This also gives us the opportunity to look at price breaks for large orders and move an item from one supplier to another, if that makes sense. At this point we usually make a cup of tea and reward ourselves with an “impulse buy” or two, if that doesn’t push us up into a higher shipping cost bracket or blow the budget. We place our orders online these days, nice and early, to increase the chances of getting exactly what we want.

Here are a few more thoughts on crops to consider:

  1. Insurance crops that are there when you need them

Young Bright Lights chard.
Photo Pam Dawling

For an overall sense of success, grow some “Insurance Crops”. These are reliable vegetable crops that grow without much attention and quietly wait until needed. Chard is one of those. We sow chard in April, after the early spring rush. We plan for it to provide us with leafy greens in the summer, after the brassicas have bolted. We prepare a bed, unroll hay mulch over it, then make “nests” in the hay for planting. Nests are holes in the hay down to soil level, at each spot where we want to plant. After transplanting. we water and tuck the hay tight around the plants to keep the weeds at bay. Some years there isn’t much demand for chard and we just leave it growing. If we need it, there it is with a generous supply of leaves. If we ignore it, nothing goes wrong. It’s worth having some crops like this in the garden, to help ensure there’s always something to eat.

Malabar spinach.
Photo by Southern Exposure Seed Exchange

One year we grew Malabar spinach and it played a similar role: hot weather leafy cooking greens. Malabar can be used when small for salads, or when larger for cooking. It wasn’t hugely popular in either role, but it was beautiful. To be fair, I don’t think we did the best by it. Because it was new, and because it had the word “spinach” in its name, some cooks served large leaves for salad. Alone. I don’t recommend that.

Purple Pod asparagus bean,
Credit Southern Exposure Seed Exchange

Another insurance crop for us is asparagus beans, also known as yard long beans. Once trellised, the plants need no attention, other than regular picking. If not picked, the pods grow puffy and useless, so this is not a crop to ignore for too long. Asparagus beans are related to southern peas (cowpeas), and are more resistant to Mexican bean beetles than regular green beans are. They do need trellising, but once you’ve done that, the same plants will feed you all season. Very little seems to trouble them.

West Indian gherkins on a trellis.
Photo by Nina Gentle

While we’re on the topic of crops that do need trellising, but can then produce all season, I’ll add in the West Indian gherkins. I found I did need to tuck these plants into the netting, so they weren’t work free. But the plants were disease-free and very productive. If you have trouble with regular pickling cucumbers, you might sow some of these as well, to be sure of being able to have something to pickle.

Another insurance crop is Tokyo bekana, or its cousin Maruba Santoh in late summer as a substitute for lettuce. It can be hard to germinate lettuce in hot weather, but these tender brassicas germinate under hot conditions and produce fast-growing very tender leaves with crunchy stems. Some people don’t know they’re not eating lettuce!

Tokyo bekana and spinach in October.
Photo Wren Vile

Senposai is a cooking green that does well in spring and fall outdoors, and in our hoophouse in the winter. It’s fast-growing, productive, disease-resistant, easy to cook and delicious to eat.  In spring it needs an early start in our climate, so that it has time to be productive before it bolts. In fall it’s cold-hardy down to 12F.  Its Achilles Heel is that it can really attract Harlequin bugs! We did spend time every day for a while squashing the bugs on the senposai leaves, and we made a difference in the number of bugs.

Well, I hope this has given you some thoughts about ordering seeds of some insurance crops for next year, when you plan your seed order.

  1. VEGETABLE CROPS THAT OFFER FAST RETURNS

Because things can go wrong in agriculture, (we are, after all, not in control of the universe!) I like to have on hand seeds for fast-growing crops that can fill unexpected gaps.

Some Eat-All Greens in early November.
Photo Lori Katz
  1. Eat-All Greens

Carol Deppe, in her delightful book The Tao of Vegetable Gardening introduces us to the concept of Eat-All Greens. Carol grows these by broadcasting seed of one of her carefully chosen greens crops in a small patch. When it reaches 12″ tall, she cuts the top 9″ off for cooking, leaving the tough-stemmed lower part, perhaps for a second cut, or to return to the soil. I wanted to try this idea in Virginia, where the climate is fairly different from the Pacific Northwest where Carol lives. I decided fall was a promising time of year to try this scheme, as our spring planted greens only have a short season before they bolt. And summer is too hot, winter too cold. . . We sowed in mid-September.

These can also be insurance crops, in that, if you don’t need them, you can cut and compost them, to let fresh leaves grow. I wrote three posts on Eat-All Greens, because they were such fun and so productive

Garlic Planting and Freeing Trapped Shoots

Garlic planting crew.
Photo Valerie Renwick

Planting Garlic

We are planting garlic, a topic I’ve written much about! Here are links to a few of my Allium of the Month posts from 2018-2019 and my slideshow.

Sign up for the free Growing for Market newsletter  and read my article How and when to plant garlic this month. That article mentions Get ready for garlic planting which you can read if you are a Full Access Member. I wrote these articles back in 2012, so I do have some newer info in my slideshow and my blog posts from last year.

See last year’s Alliums for November for

How Much Garlic to Plant

Popping Garlic Cloves for Planting;

Pre-plant Seed Garlic Treatments to reduce pests and diseases.

Planting garlic cloves, using a 5″ (13 cm) measuring stick.
Photo Brittany Lewis

Preparation for Garlic Planting

Cloves for planting should be from large (but not giant) bulbs and be in good condition. Garlic for planting should be separated into cloves 0–7 days before planting. Twist off the outer skins and pull the bulb apart, trying not to break the basal plate of the cloves (the part the roots grow from), as that makes them unusable for planting. With hardneck garlic, the remainder of the stem acts as a convenient lever for separating the cloves. We sort as we go, putting good size cloves for planting in big buckets, damaged cloves in kitchen buckets, tiny cloves in tiny buckets and outer skins and reject cloves in compost buckets. Don’t worry if some skin comes off the cloves — they will still grow successfully. The tiny cloves get planted for garlic scallions (see below).

When to Plant Garlic

Both hardneck and softneck garlic do best when planted in the fall, though softneck garlic may also be planted in the very early spring if you have to (with reduced yields). If you miss the window for fall planting, ensure that your seed garlic gets 40 days at or below 40°F (4.5°C) in storage before spring planting, or the lack of vernalization will mean the bulbs will not differentiate (divide into separate cloves).

Plant when the soil temperature at 4″ (10 cm) deep is 50°F (10°C) at 9 am. If the fall is unusually warm, wait a week.  We plant in early-mid November. (We used to plant at the end of October or early November, but we’ve moved later.) In New Hampshire, mid-October is the time. The guideline for areas with cold winters is 2-3 weeks after the first frost but before the ground freezes solid for the winter. In Michigan, planting time is 6 weeks prior to the ground freezing, giving enough time for root growth only, to avoid freezing the leaves.Instructions from Texas A&M say less than 85°F (29°C) at 2″ (5 cm) deep. In California, garlic can be planted in January or February.

Closing the furrows over the garlic cloves.
Photo Brittany Lewis

Mulch your Garlic Beds

After planting, pull soil over the cloves, tamp or roll to get the cloves in good soil contact to help the roots grow. Within a couple of days, mulch the beds. At planting time, the soil is still warm, and the newly separated cloves are now primed to start growing. If you want to roll out mulch as we do (big round bales of spoiled hay), then you need to act before fragile garlic shoots emerge from the soil. If you are using loose mulch you can blow or throw it over the beds, and a few emerged shoots are no big deal.

Garlic Scallions

Garlic scallions are small garlic plants, mostly leaves, the garlic equivalent of onion scallions (bunching onions, spring onions, escallions). Great for omelets, stir-fries, pesto, soups, and many other dishes. If you want to have Garlic Scallions to eat or sell in early spring, when new fresh vegetables are in short supply, and homesteaders may be running out of stored bulb onions, see my post Alliums for March.

You could plant these next to your main garlic patch, or in a part of the garden that’s easily accessible for harvest in spring. We plant our small cloves for scallions at one edge of the garden, and as we harvest, we use the weed-free area revealed to sow the lettuce seedlings for that week.

Planting garlic scallions is simplicity itself! Plant small cloves close together in closely-spaced furrows, simply dropping the cloves in almost shoulder to shoulder, any way up that they fall. (If you’ve just finished a large planting of main-crop garlic, you’ll probably be too tired to fuss with them anyway!) Close the furrow and mulch over the top with spoiled hay or straw.

November-planted garlic scallions in February.
Photo Pam Dawling

With a last frost date of 20–30 April, we harvest garlic scallions March 10 to April 30 in central Virginia, or even into May, if our supply lasts out, and we don’t need the space for something else. Harvesting is simple, although depending on your soil, you may need to loosen the plants with a fork rather than just pulling. Trim the roots, rinse, bundle, set in a small bucket with a little water, and you’re done!

Rather than dig up whole garlic scallion plants, some people cut the greens at 10″ (25 cm) tall and bunch them, allowing cuts to be made every two or three weeks. We tried this, but prefer to simply lift the whole plant once it reaches about 7″–8″ (18–20 cm). The leaves keep in better condition if still attached to the clove. Scallions can be sold in small bunches of three to six depending on size. A little goes a long way! If you do have more than you can sell in the spring, you could chop and dry them, or make pesto for sale later in the year.

Garlic scallions ready for harvest in early spring.
Photo Wren Vile

Cold-hardiness of Young Garlic Plants

  • At 12°F (−11°C): garlic tops that have grown fairly large will die
  • At 5°F (−15°C): garlic tops if still small will die.
  • When properly planted, cloves can withstand winter lows of –30°F (–35°C).
  • Garlic roots will grow whenever the ground isn’t frozen
  • Garlic tops will make growth whenever the temperature is above 40°F (4.5°C).

If the tops do get frozen back, do not despair! They will regrow. The growing point of alliums (garlic, onions and relatives) is close to the bulb, probably under mulch, certainly in or close to the soil, where temperatures are warmer. If your garlic gets frozen back twice, the yield will be less than if it had not got frozen, but we don’t control the weather. If your climate is getting colder in the garlic-planting season, plant deeper and/or earlier. But don’t plant earlier if climate change is giving you hotter fall weather!

Garlic shoots poking through the mulch in January.
Photo Pam Dawling

Free Trapped Garlic Shoots

See last year’s Alliums for December for my post  Free trapped garlic shoots.

Watch your mulched garlic beds and when the shoots start to emerge, choose the moment to free any trapped shoots, by working along the rows, investigating each spot where you expect a garlic plant to be, but nothing has emerged. Your goal is simply to let the shoot see the daylight. Then it will right itself. Don’t reveal any bare soil, as that will grow weeds (and let colder winter air at the garlic.) Don’t over-work this – as soon as any part of a shoot is visible, leave that plant alone, and move on to the thousands of others. It isn’t necessary to make all the leaves visible, or to clear around the whole plant.

Choosing the right time is tricky. I used to say when half or more of the shoots are visible, but one year we were having a crop disaster, and we waited too long – we were never going to have half visible. Usually, most of them emerge at the same time. it would be helpful to note down how many weeks after planting this is likely to be. We somehow haven’t done that – I think it’s about 3 weeks. Leave a comment if you have an answer!

 

Alliums for November: Plant garlic, sow onions in a hoophouse, eat leeks

Tadorna winter leeks in October.
Photo Pam Dawling

Cold-Tolerance of Alliums

Alliums are more cold-tolerant than most people believe. Here are my observations of killing temperatures for outdoor crops. Note that crops often survive night-time lows in the hoophouse that would have killed them outdoors.

  • 12°F (−11°C): garlic tops if fairly large, most fall or summer varieties of leeks (Lincoln,King Richard), large tops of potato onions
  • 10°F (−12°C) some leeks (American Flag aka Musselburgh and Scottish Flag, Jaune du Poiteau)
  • 5°F (−15°C): garlic tops if still small, some leeks (Bulgarian Giant, Laura, Tadorna, Bandit), some bulb onions, potato onions and other multiplier onions
  • 0°F (−18°C): chives, garlic, a few leeks (Alaska, Durabel); some bulb onions, yellowpotato onions, some onion scallions (Evergreen Hardy White, White Lisbon), Walla Walla onions sown in late summer (with rowcover for winter)

Planting Garlic

Planting garlic.
Photo Brittany Lewis

You can see my garlic slideshow for more info. I was surprised to find I haven’t written much in my blog about planting garlic, so here goes! See the alliums chapter in Sustainable Market Farming for more on types, varieties, and garlic genetics. The information here comes form that chapter.

When to Plant Garlic

Plant when the soil temperature at 4″ (10 cm) deep is 50°F (10°C) at 9 am. If the fall is unusually warm, wait a week. Instructions from Texas A&M say less than 85°F (29°C) at 2″ (5 cm) deep. We plant in early November. In New Hampshire, mid-October is the time. The guideline for areas with cold winters is 2-3 weeks after the first frost but before the ground freezes solid for the winter. In Michigan, planting time is 6 weeks prior to the ground freezing, giving enough time for root growth only, to avoid freezing the leaves. In California, garlic can be planted in January or February.

Both hardneck and softneck garlic do best when planted in the fall, though softneck garlic may also be planted in the very early spring if you have to (with reduced yields). If you miss the window for fall planting, ensure that your seed garlic gets 40 days at or below 40°F (4.5°C) in storage before spring planting, or the lack of vernalization will mean the bulbs will not differentiate (divide into separate cloves).

Garlic shoots emerging from the mulch a few weeks after November planting. Photo Twin Oaks Community

Garlic roots will grow whenever the ground is not frozen, and the tops will grow whenever the temperature is above 40°F (4.5°C). In colder areas the goal is to get the garlic to grow roots before the big freeze-up arrives, but not to make top growth until after the worst of the weather. In warmer areas, the goal is to get enough top growth in fall to get off to a roaring start in the spring, but not so much top growth that the leaves cannot endure the winter. If garlic gets frozen back to the ground in the winter, it can regrow and be fine. If it dies back twice in the winter, the yield will be lower than it might have been if you had been luckier with the weather. When properly planted, it can withstand winter lows of –30°F (–35°C). If planted too early, too much tender top growth happens before winter. If planted too late, there will be inadequate root growth before the winter, and a lower survival rate as well as smaller bulbs.

How Much Garlic to Plant

A yield ratio of 1:6 or 7 seems typical, and makes complete sense when you consider you are planting one clove to get a bulb of 6–7 cloves. Divide the amount you intend to produce by six to figure out how much to plant. For large areas 750–1,000 lbs/ac (842–1,122 kg/ha) are needed for plantings in double rows, 3″–4″ in-row (7.5–10 cm), beds 39″ (1 m) apart. For single rows, 8 lbs (3.6 kg) of hardneck or 4 lbs (1.8 kg) of softneck plants about 100′ (30 m). In the US, one person eats 3–9 lbs (1.4–4.2 kg) per year.

Popping garlic cloves in preparation for planting
Photo  Southern Exposure Seed Exchange

Popping Garlic Cloves for Planting

The garlic for planting should be taken apart into separate cloves 0–7 days before planting. We are doing this on November 7, along with our crop review meeting when the crew meets to make notes on the past season. This task is a good group activity. Twist off the outer skins and pull the bulb apart, trying not to break the basal plate of the cloves (the part the roots grow from), as that makes them unusable for planting. With hardneck garlic, the remainder of the stem acts as a handy lever for separating the cloves. We sort as we go, putting good size cloves in big buckets, damaged cloves in kitchen buckets, tiny cloves in tiny buckets and outer skins and reject cloves in compost buckets. The tiny cloves get planted for garlic scallions. Don’t worry if some skin comes off the cloves — they will still grow successfully. Cloves for planting should be from large (but not giant) bulbs and be in good condition.

Click the link to read about hot water treatment for seed garlic at WeeBee Farms. 

Pre-plant Seed Garlic Treatments

Many of us do nothing special with the cloves before planting, but if you have pest and disease problems, use pre-plant soaking treatments, usually done the night before planting. Some growers find they get better yields from treated cloves even if no problem was obvious.

To eradicate stem and bulb (bloat) nematode (Ditylenchus dipsaci), soak the separated cloves for thirty minutes in 100°F (37.7°C) water containing 0.1% surfactant (soap). Or soak for twenty minutes in the same strength solution at 120°F (48.5°C), then cool in plain water for 10-20 minutes.

Allow to dry for 2 hours at 100°F (37.7°C) or plant immediately. Anytime your garlic grows poorly and you can’t tell why, send a sample with the soil it’s growing in to your Extension Service to be tested for nematodes. Mites can eat the skins of the cloves, survive the winter and multiply all spring long, seriously damaging or even killing your crop. To kill mites (which hide between the wrappers) before planting, separate the bulbs into cloves and soak them overnight (up to 16 hours) in water.

Possible additions to the water include one heaping tablespoon of baking soda and one tablespoon of liquid seaweed per gallon (around 8 ml baking soda and 4 ml liquid seaweed per liter). Just before planting, drain the cloves and cover them in rubbing alcohol for three to five minutes, long enough for the alcohol to penetrate the clove covers and kill any mites inside. Then plant immediately. The long soaking will loosen the clove skins so that the alcohol can penetrate. Mite-infested garlic soaked like this does much better than unsoaked infested garlic. The solution used to kill mites can also be used to kill various fungal infections. The cloves need only fifteen to thirty minutes soaking.

In trials comparing treated and untreated cloves, treated cloves were larger and healthier than untreated ones. Fusarium levels can be kept down by adding wood ashes when planting and then possibly dusting the beds with more ashes over the winter (use moderation — don’t add so much that you make the soil alkaline). Or you could soak the cloves in a 10% bleach solution, then roll them in wood ash (wear gloves for handling ashy cloves). The wood ash soaks up the dampness of the bleach and provides a source of potassium. This information came from the Garlic Seed Foundation. Join GSF to find out all the details!

Other November Allium Planting

Plant shallot bulbs before the end of November and medium-sized potato onions (1.5″ – 2″, 4-5 cm) at the end of November or early December in zone 7. Finish dividing and replanting perennial leeks and Egyptian walking onions this month

Young onion plant in March.
Photo Kathryn Simmons

Special Allium Topic for November: Sow Bulbing Onions in the Hoophouse

We developed a system of growing onion starts in our hoophouse over the winter and transplanting them bare-root outdoors in very early March. I wrote about choosing onion varieties for your latitude last month. There I explained that to grow big onions we need to have large transplants on March 1, so we can have big vegetative plants before bulbing is triggered by the daylength.

The method involves making two sowings of bulbing onions, each enough for the whole planting. This provides insurance in case one date turns out better than the other. Then we follow this up with a partial third sowing to make up numbers of any varieties that didn’t germinate well. We make our first sowing November 10, our second November 20, and a third on December 5 as a back-up in case of problems. Our formula is: divide the number of onion plants wanted by 20, to give minimum length of row to sow, in feet. And sow this amount twice, 10 days apart. The onions will be planted out at 4″ (10 cm) apart. We add 20% to provide some slack. For a final row of 100′ (30.5 m), we’d need 100′ × 3 per foot × 1.2 (adding 20%) plants. 360 plants. We sow 3 seeds per inch (approx. 1 cm apart), 36 per foot (30 cm). At this sowing rate, we need 120″, or 10′ (3 m).

See The Year-Round Hoophouse for more on growing onions this way. If we find ourselves with extra onion plants in March, we usually re-categorize them as scallions. But we have also transplanted them in early March in a single row along the south edge of hoophouse beds, for an early crop. We got good onions but they dwarfed the pepper plants behind them. Maybe planting them on the north side of the bed is better?

Trimming roots from a leek in December.
Photo Pam Dawling

Storing Leeks

I wrote about how to dig up leeks last month. In zone 7 we leave our leeks in the ground till we need them, being sure to harvest the less hardy Lincoln and King Richard first. We use a walk-in cooler for short term storage (up to a week) and keep the root ends in water. Leeks are best stored at 33°F (0.5°C) and 65% relative humidity. In colder zones, leeks can be harvested and stored in a root cellar or basement. This is helpful in areas where the ground freezes solid for weeks on end. You can store leeks with the roots packed in soil, shoulder to shoulder in a crate or box in a root cellar, where they will keep for six weeks. They can be stored in plastic bags for two to three months at the right temperature, or frozen. Another possibility is to leave them in the garden, mulched with a foot (30 cm) of straw or hay as well as rowcover, if temperatures are below 10°F (–12°C). Our winter temperatures fluctuate a lot, so covering in-ground crops with mulch doesn’t work well for us.