Lettuce Growing Tips

 

Our first outdoor lettuce bed in May.
Photo Wren Vile

 Lettuce growing conditions – germination

  • Lettuce seed needs light to germinate – don’t sow too deep: 1/4″–1/2″ (6–10 mm) is ideal.
  • Minimum soil temperature for germination is 35°F (1.6°C).
  • Optimum temperature range for germination is 68°F–80°F (20°C–27°C). I have a table of optimum soil temperatures for germination in my book The Year-Round Hoophouse
  • Germination takes 15 days at 41°F (5°C), 7 days at 50°F (10°C), 3 at 68°F (20°C), only 2 days at 77°F (25°C)
  • Germination takes 3 days at 86°F (30°C), but will not occur reliably at temperatures hotter than that.
  • A soil thermometer soon pays for itself and saves lost crops and frustration.

Lettuce crop requirements

  • Free-draining soil, high organic matter, pH 6.0–7.0.
  • Fertile soil with good tilth will help roots grow.
  • Don’t overdo the nitrogen – encourages E. coli.
  • Keep lettuce growing quickly for good flavor – plenty of water throughout its growth.
  • Ideal growing temperatures 60°F–65°F (15°C–18°C).
  • Some growth whenever the temperature tops 40°F (4.5°C).
  • Cultivate regularly and shallowly to remove weeds.
Lettuce nursery bed with soil thermometer behind the sheep
Photo by Bridget Aleshire

Sowing lettuce for transplanting

  • You can sow in cell-packs or plug flats, 3 seeds per 1″–2″ (2.5–6 cm) cell, later reducing to 1 seedling with scissors.
  • If suitable germination space is limited, sow seed in a small flat or shallow pot, then spot the tiny seedlings into bigger flats or 606-cell packs (2″ × 2″, 5 × 5.6 cm) to grow on before planting out.
  • Can use an outdoor nursery bed from mid-April to October, rather than flats. Transplant the bare-root plants directly from the seedbed.
  • But in very hot weather, indoor sowings might give more reliable germination.

Transplanting lettuce

  • Harden off before transplanting.
  • Transplant lettuce seedlings at 4–6 true leaves, 3–6 weeks of age depending on how fast they are growing.
  • Handle transplants only by their leaves or the root ball—try not to touch the roots or stem. This minimizes the damage from your hands.
  • 8″–12″ (20–30 cm) spacing for full-sized heads. Close spacing lets foliage cover the bed completely, creating a cooler microclimate.

Lettuce Types

  1. Iceberg (crisphead) lettuces have little nutritional value. They have no frost tolerance because of their high water content. 75-100 days from direct seeding.

    Buttercrunch Bibb lettuce. Photo Kathleen Slattery
  2. Butterheads (bibbs) have very tender leaves, but have shorter shelf-life than romaines and leaf varieties. 60-75 days from direct seeding.
  3. Romaine (cos) lettuces are upright, often very crisp and flavorful. They have more vitamins than other lettuce types. &0 days or more from direct seeding.

    Green Forest romaine lettuce.
    Photo Pam Dawling
  4. Leaf lettuces include the familiar oak-leaf types, and frilly ones. You can harvest individual outer leaves or cut the whole plant. 45-60 days from direct seeding.
  5. Batavian lettuces (summer crisp or French crisp) are tasty, thick-leafed varieties that have great heat and cold tolerance. Although sometimes classified with icebergs as crisphead types, they are very different.
  6. Multileaf lettuces – familiar Tango, Panisse and Oscarde, and the newer Salanova, Multileaf and Eazyleaf brands. They are bred for uniformly small leaves, with more texture, loft and flavor than baby mixes and faster harvesting. Transplanted 6″–8″ (15-20 cm) apart they produce 40% more than baby leaf mixes. The full-size plant can be harvested as a head, providing a collection of bite-sized leaves. Or just one side (or the outer leaves) of the plant can be cut and the plant will regrow for future harvests. Growing multileaf heads takes 55 days, compared to 30 days for baby lettuce. For the most harvest, pick the outer leaves and let the middle regrow.

    Ezrilla Tango-type one-cut multileaf type lettuce
    Photo High Mowing Seeds
  7. Baby lettuce mix, aka mesclun, salad mix, spring mix and misticanza. Some mixes include other greens. 21 days from seeding in mild weather. Up to 63 days in cold weather.

Lettuce varieties for every time of year

We used to reckon on five lettuce seasons, but with climate change, our Early Spring shrank and became encompassed in our Spring, so now we have 4 lettuce seasons, and we always sow 4 diverse varieties:

  • Spring (Jan 17 – April 22), 8 sowings. Priorities: fast growth, cold tolerance
  • Summer (April 23 – Aug 14), 20 sowings (lots of seed!). Priority: extreme heat tolerance/bolt-resistance. I just sowed our first batch of summer varieties on April 23
  • Fall (Aug 15 – Sept 7), 9 sowings. Priorities: some warmth-tolerance, some cold tolerance
  • Winter (Sept 8 – 24), 9 sowings. Priority: cold-tolerance

Season extension techniques for lettuce in spring

  • Fast-maturing hardy varieties
  • In early spring, use transplants for earlier harvests
  • Warm microclimates (protection from prevailing winds)
  • In spring, warm the soil with black plastic mulch
  • Use rowcover
  • Harvesting early in the year might mean fast production in January and February, or it might mean starting in the fall and overwintering the plants. See my post series Lettuce of the Month, for ideas on varieties and techniques throughout the year. See here for the overview.
A stormy early spring day, garlic, rowcovered beds and our hoophouse.
Photo Wren Vile

Avoid lettuce bolting

Assess your risks and if in doubt, harvest early. Bolting and/or bitterness are more likely with

  • Under-watering,
  • Long days,
  • Mature plants,
  • Poor soil,
  • Crowding,
  • High temperatures,
  • Bolt-resistance generally goes from Leaf types (first to bolt), through Romaines, Butterheads, Bibbs, to Crispheads.
  • Vernalization—once the stems are thicker than 1/4″ (6 mm), if plants suffer 2 weeks of temperatures below 50°F (10°C), followed by a rapid warm-up.
  • Also see What makes vegetable crops bolt and how can I stop it?
You don’t want this! Bolting lettuce outdoors in July
Photo Alexis Yamashita

Keys to year-round lettuce success 

  • Store seed in a cool, dry, dark, mouse proof place.
  • Good soil preparation and high organic matter are important for high quality lettuce, which needs to grow quickly.
  • Location, location, location! We grow lettuce outside from transplants from February to December (harvesting from late April); in a solar-heated greenhouse from September to March (harvesting leaves from November) and in a solar heated hoophouse from October to April (harvesting leaves from November, and whole heads in April). We also sow baby lettuce mix in the hoophouse from October to February, for harvest multiple times from December to April.
  • Use shade cloth on hoops in hot weather
  • Use rowcover in cold weather, or plant in cold frames, greenhouses or hoophouses.

Scheduling lettuce for continuous harvests

  • Lettuce grows faster at some times of year than others, and the time between one sowing and the next needs to vary to balance this.
  • To harvest a new planting every week you need to have sowing gaps of more than 7 days in the spring, 6-7 days in the summer, less in fall.
  • In warm spring weather, baby heads of lettuce or individual leaves can be ready to harvest 4 weeks after transplanting, and full-sized heads 6 weeks after transplanting.
  • In summer, full-size heads can be ready in as little as 3 weeks from transplanting.
  • As temperatures and day-length decrease in the fall, the time to maturity lengthens, and a single day’s difference in sowing date can lead to almost a week’s difference in harvest date.
  • Lettuce for harvest in February will take 2-3 times as long from planting to harvest as that for September harvest.
  • December and January sowings grow very slowly, and early February sowings will almost catch up.
Flats of lettuce transplants in our cold frame in April.
Photo Pam Dawling

Scheduling lettuce January-June

January: sow every 2 weeks

  • Sow indoors in flats in late January for outdoor transplants
  • If you have a greenhouse or hoophouse, transplant there until mid-February
  • Harvest leaf lettuce and baby lettuce mix from protected crops

February: sow every 2 weeks

  • Same as January

March: sow every 13 days, indoors in flats

  • From late March or early April, you could switch to outdoor direct sowing. (We transplant all our lettuce.)
  • Transplant the first 3 sowings outdoors with rowcover
  • Harvest leaf lettuce, baby lettuce mix from a hoophouse; starting late March, harvest leaves from the first outdoor planting

April: Sow every 9 days

  • Transplant the March sowings
  • Harvest whole heads from late April

May: Sow every 8 days

  • Transplant 1 week’s needs each week
  • Harvest outdoor heads

June: Sow every 6 or 5 days, under shadecloth

  • Transplant one week’s needs every 6 days, using shadecloth for the first 2 weeks
  • Harvest outdoor heads

See my post Lettuce All Year in a Changing Climate, which includes links to my slideshow about growing lettuce year round, and our Lettuce Varieties list and Lettuce Log (planting schedule). It also includes keys to succeeding with year-round lettuce (dates for succession planting).

Lettuce bed in May.
Photo Wren Vile

Lettuce All Year in a Changing Climate

Lettuce bed in May.
Photo Wren Vile

We like to eat lettuce year round, and have put time and energy into finding the varieties and planting dates that work best here in Central Virginia, as well as how to get the best results in each season. Recently I revised our lettuce schedules, partly to take account of hotter weather arriving earlier in the year, and also to even out the harvest dates.

I have frequently written blogposts about growing lettuce. And I have a whole year of Lettuce for the Month posts. See here for the overview, or click on the month you want to know more about. These posts are mainly about our favorite varieties for each time of year.

I have a slideshow Lettuce year round  – It’s at the end of this post.

Back in 2006, I wrote Lettuce: Organic Production in Virginia for VABF. We’re now in Winter Hardiness Zone 7a. Back then we were 6b. Read this publication for details you are hazy on, but see our updated Lettuce Varieties List and Lettuce Log in this post.

Fast-growing Red Salad Bowl lettuce.
Photo Bridget Aleshire

Choose appropriate lettuce varieties for each time of year.

Sow several varieties each time to spread the harvest season and the risks of poor germination. I like to use something fast, something slow; at least one red; a romaine, a bibb and a couple of leaf types.

Consider multileaf lettuces too, Salanova and Eazyleaf brands. They are bred for uniformly small leaves, with more texture, loft and flavor than baby mixes and faster harvesting. Transplanted 6″–8″ (15-20 cm) apart they produce 40% more than baby leaf mixes. The full-size plant can be harvested as a head, providing a collection of bite-sized leaves.  Or just one side (or the outer leaves) of the plant can be cut and the plant will regrow for future harvests. Growing multileaf heads takes 55 days, compared to 30 days for baby lettuce

Red Hawk Farm hoophouse densely planted with multileaf lettuces.
Photo Pam Dawling

Our recent changes to our Lettuce Varieties List include switching over from “Early Spring” varieties to “Spring” varieties at the end of February rather than the end of March. This means we only make 3 sowings of the early spring varieties, and we need to stop buying much seed of those varieties! Next year I might even abolish that category and those early varieties to simplify life.

The spring varieties we now sow from February 28 to April 22. We used to sow these until May 15. We’re still making 5 sowings of those, but the dates have moved earlier.

On April 23 we switch over to our Summer varieties, which we make 20 sowings of, until August 14. (Buy lots of seed of those varieties!) We then switch to nine sowings of Fall varieties, until September 7.

Lettuce growing in our greenhouse in November.
Photo Wren Vile

From September 8 to the end of September we use our cold hardy varieties. These 9 sowings include those for the greenhouse and hoophouse, which will feed us all winter. 

Click to access Lettuce-Varieties-pdf.pdf

You’ll need a large screen, a magnifying glass or the ability to expand the image.

We like to grow a balance of leaf lettuce and head lettuces, and, in winter, baby lettuce mix too. We harvest the baby lettuce mix when 3″–4″ (7.5–10 cm) tall, cutting 1” (2.5 cm) above the soil. We harvest leaves from the big lettuces the rest of the time. Baby lettuce mix is very pretty, but I actually prefer the juiciness and crunch of big lettuce.

Beautiful baby lettuce mix in our hoophouse.
photo Wren Vile

Keys to year round lettuce

  • ·         Store seed in a cool, dry, dark, mouse proof place.
  • ·         Grow your lettuce quickly, for high quality and flavor, using good soil preparation and high organic matter.
  • ·         Learn the skills of lettuce germination in all weathers. Minimum soil temperature for germination is 35°F (1.6°C).  Optimum temperature range for germination is 68°F–80°F (20°C–27°C).1/4″–1/2″ (6–10 mm) deep is ideal.  Good light.
  • Watch the temperature – Germination takes 15 days at 41°F (5°C), 7 days at 50°F (10°C), 3 days at 68°F (20°C) and only 2 days at 77°F (25°C). Germination will not occur reliably at temperatures hotter than 86°F (30°C).
  • Keep watching the temperature –  Optimum growing temperatures are 60°F–65°F (15°C–18°C), Some growth occurs whenever the temperature tops 40°F (4.5°C).
  • ·         Choose good locations! We grow lettuce outside from transplants from February to December (harvesting from late April); in a solar-heated greenhouse from September to March (harvesting leaves from November) and in a solar heated hoophouse from October to April (harvesting leaves from November, and whole heads in April). We also sow baby lettuce mix in the hoophouse from October to February, for harvest multiple times from December to April.
  • ·         Use shade cloth on hoops in hot weather
  • ·         Use rowcover in cold weather, or plant in cold frames, greenhouses or hoophouses.

Lettuce under shade cloth.
Photo by Nina Gentle

Grow a consistent lettuce supply using succession crop planting

To have a continuous supply, it is important to plant frequently, at intervals adapted for the time of year. The gap between one sowing and the next gets smaller as the year progresses; the gap between one transplanting and the next does likewise. The number of days to reach transplant size dips to 21 days in the summer, then lengthens as the weather cools and the days get shorter.

We made a Lettuce Succession Crops graph using our records for sowing date and harvest start date. From this we determined the sowing dates to provide us with a fresh harvest (120 heads of lettuce, or equivalent) every single week. We made a Lettuce Log with our planned sowing, transplanting and harvest dates. This is explained in my slideshow Lettuce year round.

Lettuce Succession Crops Graph

Click to access Lettuce-Succession-Crops.pdf

Rouge d’Hiver hardy romaine lettuce.
Photo Bridget Aleshire

Recently I fine-tuned this in light of more recent records. In some cases we had been led astray by a spreadsheet date calculator that was based on 30 day months in a 360 day year! Not reality! We also had data showing that transplants were not always ready on the dates we had thought, probably due to a mistake in an earlier year when we were unable to transplant on time, and repeated the delayed date the next year. Most of the tweaking was in early and late spring, and then in August.

Click to access Lettuce-Log.pdf

Tips for growing good quality lettuce

I recommend transplanting lettuce (other than baby lettuce mix) at 4-6 true leaves (3-6 weeks of age). It is worth learning good transplanting skills, so that plants thrive, even if transplanted in mid-summer.

Water enough, with an efficient irrigation system. Water new transplants daily for the first 3 days, then every 4-7 days after that. Lettuce needs a relatively large amount of water throughout its growth.  Deeper weekly waterings equivalent to 1” (25 mm) of rain are better than frequent superficial irrigation – roots will grow deeper, giving the plant greater drought-resistance.

To make best use of space and time, plant lettuces 10-12” (25-30 cm) apart, in a hexagonal pattern. If you plant too close, you are restricting the size of the lettuce. If you plant with more space than needed, you will waste time dealing with more weeds!

Flats of lettuce transplants in our cold frame in April.
Photo Pam Dawling

Transplanting gets a head start on weed control, which is important from planting to a couple of weeks before harvest. Don’t waste time hoeing lettuce you will be harvesting next week. I generally find that if I hoe once, a couple of weeks after transplanting, that is all the weed control I need at the fast-growing time of year. We like the stirrup, or scuffle, hoes, which are safer in the hands of novices than sharp edged hoes, because the blade is in a closed loop.

Some growers use black plastic mulch, but I hate filling the world with single use plastic, so we don’t do that. Some others use landscape fabric with melted holes at the right spacing. I used this for strawberries and liked it. I’m not sure I’d find it worthwhile for fast-growing lettuce. No-till growers can transplant into mulch, first making what we call “nests” at the appropriate measured spacing. It’s tempting to skip the measuring, but if you drift from a 12” (30 cm) spacing to a 15” (38 cm) spacing, you will end up with fewer lettuces!

For those who like to direct sow lettuce, you could prepare the bed, let it rest for a week (watering it), then flame or lightly hoe the surface before sowing to remove a flush of weeds.

Lettuce seedlings for transplanting later. Photo Pam Dawling

Bolting and/or bitterness are more likely with under-watering, long days, mature plants, poor soil, crowding, high temperatures, and vernalization—once the stems are thicker than 1/4″ (6 mm), if plants suffer 2 weeks of temperatures below 50°F (10°C), followed by a rapid warm-up.

Bolting lettuce in July
Photo Alexis Yamashita

Deal promptly with pests and diseases. Aphids, cutworms, slugs, rabbits, groundhogs and deer all like lettuce as much as we do. If you find your lettuces melting down with fungal diseases, you can, of course, commit to better crop rotation. You can also consider solarizing beds for next year’s lettuce. You need a minimum of 6 hot weeks in which to cook the soil-borne disease spores by covering the prepared beds tightly with clear plastic. Old hoophouse plastic is ideal – construction plastic does not have the UV inhibitors that prevent the plastic shattering into shards. 

More resources

Cornell has a 2016 Organic Production and IPM Guide for Lettuce 67 pages of everything you are likely to need, for growing in New York type climates, at least.

Ray Tyler at Rose Creek farm has a Lettuce Masterclass, a step-by-step blueprint to plan, grow, and sell lettuce year-round!

This slideshow is from 2019, before I made the changes I mention above.

Lettuce Year Round 60 mins

Early Lettuce Production

Young Salad Bowl lettuce
Photo Wren Vile

Early Lettuce Production

Growing early season lettuces involves choosing suitable types and varieties (cold-tolerant and fast-growing), having successful production methods, and a good schedule. Harvesting early in the year might mean fast production in January and February, or it might mean starting in the fall and overwintering the plants. See my post series Lettuce of the Month, for ideas on varieties and techniques throughout the year.

Our Climate Zone in central Virginia is 7a, which means our annual minimum temperature averages 0°F to 5°F (-18 to -15°C).  The average date of the last spring frost is April 30 (later than 5/14 one year in 10). We grow lettuce outside from transplants from February to December, in a solar greenhouse from October to early March, and in a solar-heated double-layer hoophouse from October to April.

Swordleaf, Red Salad Bowl and Bronze Arrow lettuces.
Photo Bridget Aleshire

Lettuce Types

There are several different general types of lettuces. In terms of growing speed, the baby lettuce mixes and the leaf lettuces produce harvests soonest after sowing. Loose-leaf lettuces are very useful because you can harvest individual leaves while you’re waiting for the heads to reach full size.

Leaf types are ready for harvest 45-60 days from direct seeding, 30-45 days from transplanting. Bibbs mature in 60-75 days, most head lettuce need up to 80 days from seeding, or 60-70 days from transplanting in spring. Romaines are slower-growing (70 days or more). Batavian lettuces (also called French Crisp) are tasty, thick-leafed varieties that have excellent heat and cold tolerance. Icebergs mature in 75-100 days.

Beautiful baby lettuce mix in our hoophouse.
photo Wren Vile

Baby lettuce can be cut 21 days from seeding, (except from November to mid-February, when it may take 2 or 3 times as long).

Bolt-resistance generally goes from Leaf types (first to bolt), through Romaines, Butterheads, Bibbs, to Crispheads.

I like to sow four lettuce varieties each time (for the attractive harvests, and to reduce the risks if one variety bolts or suffers disease): at least one red and one romaine. We have 5 lettuce seasons, with different varieties:

  1. Early Spring (Jan – Mar), 6 sowings
  2. Spring (April – May 15), 5 sowings
  3. Summer (May 15 – Aug 15), 17 sowings
  4. Fall (Aug 15 – Sept 7), 9 sowings
  5. Winter indoors, Sept 8 – 27, 9 sowings

 Lettuce Varieties

Bronze Arrow lettuce ultra-closeup. Photo Bridget Aleshire

It’s important to grow the right lettuce variety for the conditions. For earliest harvests, consider a different, faster, variety than you have usually grown. Some of the early spring lettuce varieties are often useless here if sown after mid-March, or even mid-February, because they bolt prematurely as the Virginia spring flips from cold to hot (and back again, grrr!). Varieties we only sow until 2/15 include Bronze Arrowhead (46 day leaf lettuce); Buckley, Ezrilla and Hampton (55d multi-leaf types); Merlot (60d), Midnight Ruffles (48d) and Oscarde (45d) (leaf lettuces). Antares (48d) Panisse (48d) and Revolution (38d) leaf lettuces we can sow until 3/15.

Nancy bibb lettuce
Photo Bridget Aleshire

Others that we like in early spring go on to be useful later in spring too. In this category are Buttercrunch (a small 50d bibb); Nancy (58d) and Sylvesta (52d) (two big green bibbs); Pirat (55d red bibb), Green Forest (56d), Kalura (57d) (two green romaines); and New Red Fire (55d), our reliable Salad Bowl (45d) and Red Salad Bowl (46d), Starfighter (52d), and Swordleaf (53d) (leaf lettuces)

New Red Fire lettuce.
Photo by Bridget Aleshire

The baby lettuce mixes we like are Fedco’s 2981 LO Lettuce Mix OG (contains at least six different lettuces) or Johnny’s Allstar Gourmet Lettuce Mix #2310 (including green and red oakleaf, green and red romaine, lollo rossa, and red leaf lettuces). One gram sows 25 ft, one ounce will sow about 600 feet.

For those with challenging growing conditions, both companies offer other specialized selected mixes.

Cold-tolerance of lettuce

Red Tinged Winter and Tango lettuce in our hoophouse in December.
Photo Pam Dawling

Lettuce is more cold tolerant than many people realize. If plants are sufficiently hardened (prepared by growing in gradually lower temperatures), they can withstand freezing. At 22°F (-6°C), large leaves of some lettuce will die. Medium-sized plants with 4-10 leaves (Marvel of Four Seasons, Olga, Rouge d’Hiver, Tango, Winter Density may survive unprotected down to 15°F (-9.5°C). Half-grown lettuces are more cold-hardy than full-sized plants.

Lettuce Crop Requirements

Flats of lettuce transplants in our cold frame in April.
Photo Pam Dawling

Lettuce seed remains dormant unless triggered by adequate levels of light and temperature. It needs light to germinate, so don’t sow too deep: ¼-3/8″ (6-9 mm) is enough. Some sources recommend not covering the seed at all, but this can make it hard to keep the seed damp. The light dormancy is more pronounced in fresh seed, which has higher levels of the hormone that controls germination.

Soil temperature is important. I have a table of optimum soil temperatures for germination in The Year-Round Hoophouse The optimum temperature range for lettuce germination is 68-80°F (20-27°C). It takes 7 days to germinate with a soil temperature of 50°F (10°C) or 15 days at 41°F (5°C), and only 4 days at 59°F (15°C). Even a few hours at temperatures higher than the optimum can induce dormancy.

Lettuce transplants prefer a well-draining soil high in organic matter, and with a pH of 6.0-7.0, not lower. Optimum growing temperatures are 60-65°F (15-18°C), with a minimum of 40°F (4.5°C) for any growth to occur. Lack of water will lead to bolting, and/or bitterness. Keep them growing quickly for good flavor.

Lettuce in January

A flat of newly emerged lettuce seedlings
Photo Kathryn Simmons

We plan to start harvesting heads of lettuce outdoors from April 15. Before then we will harvesting lettuce in our greenhouse and hoophouse.

In mid-January we sow four lettuce varieties, to become our first outdoor transplants. I recommend sowing several varieties each time to spread your risks, if one kind bolts or suffers disease. I choose varieties that cover the range of colors and shapes. I select hardy types that are fast-maturing. Buttercrunch green bibb lettuce is one of my favorites for early spring. One of the Salad Bowl lettuces, red or green, is also usually in my first sowing. The Salad Bowls are so reliable and productive! New Red Fire has become another reliable lettuce stand-by for us. It was suggested to me by neighboring Virginia farmer, Gary Scott of Twin Springs Farm. It is more of a leaf lettuce, and doesn’t exactly head up, although it can be cut as admittedly lightweight heads. It works fine as a leaf lettuce, harvested by the cut-and-come-again method. We grow New Red Fire year round, it’s that adaptable and easy-going. We haven’t found many good full-size red romaines. Bronze Arrow  has worked well for us and we were harvesting it in early May.

We grow all our outdoor lettuce as transplants. In spring we sow in 3″ (7.5cm) deep open wood seed flats, 12″ x 24″ (30 x 60cm). We make four little furrows by pressing a 12″ (30 cm) plastic strip (aka a ruler!) into the seed compost. We sow the seed, label it, cover it lightly, water, and put the seeded flats in our germinator cabinet. The first flat of the year takes about 9 days to germinate.

Spotting cabbage seedlings from a seed flat into a transplant flat.
Photo Wren Vile

Once the seedlings are big enough to handle, we spot them out into 4″ (10 cm) deep flats (also 12″ x 24″/30 x 60cm). We have a plywood dibble board with pegs evenly spaced about 2.5″ (6 cm) apart. We aim to harden off the lettuce for two weeks in the cold frame before transplanting into the garden beds with thick rowcover on hoops to protect the lettuce from the still-cold outdoors. To be ready for harvest 4/15, these seeds have to become full size lettuces in 88 chilly days.

Seeds can instead be sown in cell packs or plug flats, putting three seeds in each cell, and later reducing to one seedling with scissors. Cells or pots with diameters from 1-2½” (2.5-6cm) can be used. The 96-cell size (1×1½”/2.5x4cm) works well, although the 200-cell size (1×1”/2.5×2.5cm) is possible if you can be sure to get the transplants out before they get root-bound. If warm germination space is limited in early spring, sow seed in a small flat, then “spot” the tiny seedlings into bigger flats, 606 (2×2¼”/2.5x6cm) cell packs, or 32-pack square pots to grow on in cooler conditions before planting out. Soil blocks are also possible, but take more time.

We make a second sowing on January 31. The intervals between sowings at the beginning of the year are long, because later sowings will catch up to some extent with earlier ones. Most crops grow faster in warmer weather.

Lettuce in February

We sow lettuce twice in February – 14 days apart. We get ready to transplant our first outdoor lettuce, to feed us mid-late April. Our first sowing of baby lettuce mix in the hoophouse comes to the bitter end, and the second sowing is awaited. We continue to harvest leaves from the large lettuce we transplanted in the hoophouse in October.

Lettuce in March

Lettuce with sclerotinia drop.
Photo Pam Dawling

We sow flats of lettuce every 10 days in March. March 9 is our goal for a transplanting date outdoors for our first 120 lettuce (about one week’s worth for 100 people).

Here is a link to a helpful publication from eXtension: Disease Management in Organic Lettuce Production. Horribly useful photos!

Baby Lettuce Mix

Baby lettuce mix can be ready in as little as 21 days from mid-spring to mid-fall, longer in early spring. A direct-sown cut-and-come-again crop, the plants regrow and can be harvested more than once in cool seasons. We sow 10 rows in a 4’ (1.2m) bed, 4.5” (11cm) apart. Weed and thin to 1″ (2.5 cm). When 3″–4″ (7.5–10 cm) tall, cut 1” (2.5 cm) above the soil. Gather a small handful in one hand and cut with using large scissors. Immediately after harvesting, weed the just-cut area so the next cut won’t include weeds. Rake after harvest with a fine leaf rake to remove outer leaves and cut scraps. If you want to make more than one cut, you will need to remove anything that isn’t top quality salad while you can see it. Larger scale operations have harvesting machines.

 

Lettuce Varieties for 2017

We’ve just updated our Lettuce Varieties List for 2017, removing ones that didn’t do well last year, highlighting ones that did do well, and checking which dates work for which varieties in our climate (central Virginia, cold-hardiness zone 7).

I tried to paste in the list, but failed (I know I’ve done it successfully before!) so here’s a link and some photos

Lettuce Varieties

Reliable Red Salad Bowl lettuce, one of our stand-bys.
Photo Bridget Aleshire
Young Parris Island romaine lettuce.
photo Bridget Aleshire
Lollo Di Vino lettuce, developed by Wild Garden Seeds. Photo by https://www.wildgardenseed.com
Merlot red lettuce, from Wild Garden Seeds. Photo by https://www.wildgardenseed.com

 

 

 

 

 

 

 

When I posted my Lettuce Varieties for January article, Wanda commented on the great varieties available from Frank Morton at wildgardenseeds.com. They do have some wonderful lettuces, so I’ve included a couple of pictures of their varieties  that we grow, above.


I’m short of time today, I’m getting ready for the Southern Sustainable Agriculture Working Group Conference. Check out my Events page for more about what I’m doing there. Two brand new workshops, and book signing. I hope to see some of you bringing your dog-eared and mud-splattered copies of Sustainable Market Farming for signing on Thursday evening. I’d love some photos of well-used copies of my book!

Lettuce varieties for January, new year, fresh start

Newly germinated lettuce seedlings. Photo Kathryn Simmons
Newly germinated lettuce seedlings.
Photo Kathryn Simmons

Maybe you aren’t ready to think about sowing lettuce, but I am! In mid-January we sow a flat of four lettuce varieties, to become our first outdoor transplants. I like to choose four varieties that cover the range of colors and shapes.

Buttercrunch bibb lettuce. Photo Kathleen Slattery
Buttercrunch bibb lettuce. Photo Kathleen Slattery

I also like to choose hardy types that are fast-maturing. Buttercrunch green bibb lettuce is one of my favorites for early spring. One of the Salad Bowl lettuces, red or green, is also usually in my first sowing. The Salad Bowls are so reliable and productive!

Young Salad Bowl lettuce. Photo Bridget Aleshire
Young Salad Bowl lettuce.
Photo Bridget Aleshire

New Red Fire has become another reliable lettuce stand-by for us. It was suggested to me by neighboring Virginia farmer, Gary Scott of Twin Springs Farm. It is more of a leaf lettuce, and doesn’t really head up, although it can be cut as admittedly lightweight heads. And it works fine as a leaf lettuce, to be harvested by the cut-and-come-again method. We grow New Red Fire year round, it’s that adaptable and easy-going.

New Red Fire lettuce. Photo by Bridget Aleshire
New Red Fire lettuce.
Photo by Bridget Aleshire

After last year’s success with Sword Leaf lettuce, which I wrote about last May, we have added this variety to our list of favorite lettuce varieties. But if I start those four, I won’t have a romaine and will have only one red. We haven’t found many good full-size red romaines. Rouge d’hiver is a possibility, although I wonder if it would bolt too easily (it’s more famous for growing in winter). A better choice might be Bronze Arrow (it worked well last year and we were harvesting it in early May).

We expect/intend/plan to start harvesting heads of lettuce outdoors starting 4/15. Before that we will harvesting the lettuce in the greenhouse and the hoophouse.

As you see from the top photo, we grow our outdoor lettuce as bare root transplants, starting in open flats. I’ll write about bare root transplants next week. We find it an easy, forgiving method for many crops.  For now, I’ll just talk about the lettuce. We sow in 3″ deep open wood seed flats, 12″ x 24″. We make four little furrows by pressing a 12″ plastic strip (aka a ruler!) into the seed compost. We sow the seed, label it, cover it lightly, water, then put the seeded flats in our germinator cabinet. The first flat of the year takes about 9 days to germinate. According to tables in Nancy Bubel’s Seed Starter Handbook and in Knott’s Vegetable Growers’ Handbook available free online as a pdf here, lettuce takes 7 days to germinate with a soil temperature of 50F (10C) or 15 days at 41F (5C), and only 4 days at 59F (15C).

Once the seedlings are big enough to handle, we spot them out into 4″ deep flats (also 12″ x 24″). We have a plywood dibble board with pegs evenly spaced about 2.5″ apart. You can see the offset pattern in this next photo:

Lettuce seedlings spotted out into deep flats. Photo Kathryn Simmons
Lettuce seedlings spotted out into deep flats.
Photo Kathryn Simmons

We aim to harden off the lettuce for two weeks in the cold frame before transplanting into the garden beds with thick rowcover on hoops to protect the lettuce from the still-cold outdoors. To be ready for harvest 4/15, these seeds have to become full size lettuces in 88 chilly days.

We make a second sowing on 1/31. The intervals between sowings at the beginning of the year are long, because later sowings will to some extent catch up with earlier ones. Almost all crops grow faster in warmer weather (up to a point). We sow lettuce twice in February (every 14 days), then every 10 days in March, reducing the interval down to every 6 or 7 days by the summer.

As far as varieties go, we think of The Lettuce Year as having 5 seasons: Early Spring January – March, Spring April 1 – May 15, Summer May 15 – Aug 15, fall August 15 – September 7 and Winter September 8 till the end of September and our break from sowing lettuce.

Some of the early spring lettuce varieties will bolt prematurely here if sown after March 31. Examples include Bronze Arrow, Freckles, Merlot, Midnite Ruffles, Oscarde and Panisse.

Others that we like in early spring go on to be useful in spring too. All the ones mentioned as possibilities for sowing #1 are in this category, as are Green Forest, Parris Island, Kalura (three green romaines), Nancy and Sylvesta (two big green bibbs), Pirat (a red bibb), and Star Fighter (a green leaf lettuce)

Freckles lettuce has to be sown here before the end of March, or it bolts prematurely. Photo Kathryn Simmons
Freckles lettuce has to be sown here before the end of March, or it bolts prematurely.
Photo Kathryn Simmons

Lettuce in November, Twin Oaks Garden blog

Red Salad Bowl lettuce.. Photo Bridget Aleshire
Red Salad Bowl lettuce..
Photo Bridget Aleshire

I have written blogposts about growing lettuce in October, September, August, July, June and May. On October 25, I reported that we have covered our last outdoor bed of head and leaf lettuce, and an “emergency” bed of baby lettuce mix with double hoops and rowcover. Now, one month later, we are waiting out this cold snap (19F/-7C last night) until we get a mild spell to uncover those beds and finish harvesting them. We want to move the hoops and row covers to the outdoor spinach beds.

We are now harvesting only winter salad mixes, no more big bowls just of lettuce. We are using leaves from the outdoor lettuce, the outdoor lettuce mix, or leaves from the lettuce in the greenhouse, according to whatever is most ready. We chop the lettuce up as we harvest. I start with about half of the harvest bucket full of chopped lettuce. I notice that it takes 3 half-buckets of harvested greens to fill one bucket! The greens settle, and when mixed they take less space than they started out using.

Late October Starfighter and Red Salad Bowl lettuce in our hoophouse. Photo Wren Vile
Late October Starfighter and Red Salad Bowl lettuce in our hoophouse.
Photo Wren Vile

Lettuce varieties we are currently harvesting include Green Forest, Hyper Red Wave, Merlot, new Red Fire, Oscarde, Panisse, Red Salad Bowl, Red Tinged Winter, Revolution, Salad Bowl, Star Fighter, Tango, Winter Marvel and Winter Wonderland. Last winter we grew some Osborne Multileaf varieties we liked a lot. This year I learned the hard way that pelleted seed doesn’t store well. As pointed out by Johnnys Seeds in their JSS Advantage Newsletter January 2012

“Some seeds, particularly lettuce, are primed before pelleting, which begins the metabolic process leading to germination. Because some of the early steps toward germination are completed before the seed is planted, germination happens more quickly. Germination times can be 50% faster with primed seed. When seeds germinate quickly, they may avoid potential problems including soil crusting, weeds, and soilborne diseases. On the down side, primed seed doesn’t have the same storage life as unprimed seeds, so we recommend that you purchase only enough for the current season.”

Bulls Blood Beet leaves Photo Bridget Aleshire
Bulls Blood Beet leaves
Photo Bridget Aleshire

I like to mix three crop families in every salad mix: lettuce, spinach/chard/beet greens/brassicas. I also like to mix the colors and textures, so if most of that day’s lettuce leaves are green, I’ll be sure to get some Bulls Blood beet leaves or Ruby Streaks or Scarlet Frills. I don’t make the same mix every day, as variety is the spice of life!

Ruby Streaks. Photo Southern Exposure Seed Exchange
Ruby Streaks.
Photo Southern Exposure Seed Exchange

I love the taste of spinach leaves in salad, and we have lots of spinach (outdoors, in cold frames and in the hoophouse). I love the colors of baby Bright Lights and Rainbow chard. I chop those stems small – not everyone likes a big hit of chard flavor in their salad. When I harvest Bulls Blood beets I snip the stems close to the base of the plant, line up a handful of leaves, then snip off the stems just below the leaf blades, before chopping the leaves into the bucket. These stems are kind of wiry, not good food. I don’t like to leave the leaf stems on the plant for two reasons. One is that the stems “cage in” the developing plant, reducing the access to sunlight and photosynthesis. The other is that the stems die back later and rot. Better to remove them right away. I do the same with spinach.

Last month I mentioned the brassica salad mix we sowed in our hoophouse 10/2. We have made three cuts already – very good value for the tiny amount of space occupied. Mizuna, Ruby Streaks, Scarlet Frills and Golden Frills add a ferny shape and some loft to the mix. Mizuna is very mild, the other three are spicy. Other brassicas we are currently cutting small for our salad mixes include tatsoi and Russian kales (red and white). At some point, deeper in the winter, we’ll try to leave the kale alone to grow big for cooking greens. This will happen when we are shorter of cooking greens than salad items, and the kale has become more robust. Some of the crew are more hardcore than me, and include sturdier greens, like senposai. Later in the winter, other crops will come to the fore.

We also include as microgreens any thinnings from recently sowed rows of almost any greens, including radishes and turnips if they are not bristly-leaved varieties.

Traditional Chinese Scissors from Lee Valley
Traditional Chinese Scissors from Lee Valley

Our 10/24 hoophouse sowing of baby lettuce mix is almost ready to harvest – maybe in the next week or so. We have made an 11/2 second sowing of mizuna and friends, but the seedlings are still tiny, showing a big difference between the temperatures on 10/24 and those a week later on 11/2.

For cutting lettuce I like the plain steel scissors from Lee Valley. They are sturdy, easy to tighten and sharpen and ambidextrous. They are a traditional Chinese style.


Lastly, for those of you who want to know more about the Twin Oaks garden specifically, let me introduce you to the Twin Oaks Garden blog. It’s written by Wren Vile, one of the upcoming managers. I will be retiring as garden manager on March 1 2017, and Wren and Brittany will take over the day-to-day running of the garden. I won’t be going away, I’ll be around to answer questions, and I will continue to do some work in the garden, around the “edges”, rather than in the thick of the shifts. I’ll have more time for my writing and speaking on vegetable growing, and I’ll have more time off!

Brittany resting in the potato rows. Photo Wren Vile, https://twinoaksgarden.wordpress.com/
Brittany resting in the potato rows.
Photo Wren Vile, https://twinoaksgarden.wordpress.com/

Growing for Market February issue is out! So is USDA Climate Change Report!

GFM-February2013-cover-300px

The February 2013 issue of Growing for Market magazine is now available, including my new article  Making Good Decisions Under Pressure. This is the fourth article in my series about being resilient, understanding what’s going on with the plants and the weather, and knowing when to take action, is about tools to help busy farmers with complex decisions that have to be taken quickly. The middle of a hot field in mid-afternoon of the day you need to plant is not the best place to make a hard decision. It’s better to have a framework in place to lean on when the going gets tough. I talk about various decision-making techniques, clarifying whose job it is to make each decision, what resources are available, and what the impacts of the decision might be.

If that sounds abstract, I also include our sad chart “Can’t Do It All 2011”.  In early March that year, we realized we had nothing like enough experienced workers. We were looking at an overwhelming amount of work. We made a list of labor-intensive crops for possible cuts. The main point was to save us time, not just cut crops we personally disliked! We noted the decision date by each crop on the list. As each date approached we reviewed our situation. This method enabled us to make one decision at a time, in a straightforward way, and not go insane. Such a list is helpful for many types of calamity. It leaves the door open for possible upturns of fortune later in the year. It’s less distressing to take one bite at a time than to take a big decision when you already are struggling to cope with some big bad thing having happened.

This issue of GfM also has these articles:

• Lettuce varieties that tolerate heat and cold By Lynn Byczynski

• Book Reviews: The Organic Seed Grower (John Navazio) and The Art of Fermentation Sandor Katz) by Lynn Byczynski

• A new meal-planning service keeps CSA members happy by Lynn Byczynski

• Capturing information in the field to help with recordkeeping, by Chris Blanchard

• Plans for farm-built pallets that make it easy to move transplants, by Chip and Susan Planck

• What the proposed federal produce safety rules mean to you, by Lynn Byczynski

• An urban flower farmer builds a flourishing business in weddings, an interview with Jennie Love by Erin Benzakein.

Also newly arrived is the Report Climate Change and Agriculture in the United States: Effects and Adaptation (USDA Technical Bulletin 1935). I wrote about this in my post following the CFSA conference in October, where I attended a gripping workshop by Laura Lengnick, one of the authors of this report. It has 193 pages, and when I’ve read it, I’ll review it. Chapters include An Overview of U.S. Agriculture, An Overview of the Changing Climate, Climate Change Science and Agriculture, Climate Change Effects on U.S. Agricultural Production, Climate Change Effects on the Economics of U.S. Agriculture, Adapting to Climate Change, Conclusions and Research Needs, and various appendices.

Photo by Wren Vile

Photo by Wren Vile