Lettuce Fast Facts:
Cool or warm weather: Cool
Size: Small
Sun: 6-8 hours
Days til maturity: 45-60 days
Water: Keep soil moderately moist
Original or Leaf GreenStalk: Original or Leaf
GreenStalk level: Place above larger plants
Plant support needed? No
Homegrown salad greens taste better and last longer than store-bought. Compact and super easy to grow, with very few pests or diseases even worth mentioning, lettuce is an ideal container plant and you can grow even more of it vertically. “Lettuce” show you how!
Planting & Growing
Whether you want to grow heads of lettuce, loose-leaf spring mixes, or baby greens, we recommend you direct sow right into your GreenStalk Vertical Planter. Sprinkle seeds and lightly cover with soil or with a thin layer of vermiculite. Lettuce seeds need a little light to germinate so don’t plant too deeply. Gently mist the seeds after sowing and keep the pockets moist until the seeds sprout. Once you see germination, begin watering through the top reservoir.
Lettuce is a full-sun, cool-season crop that does best in spring and fall. Seeds will germinate in temperatures as low as 45°F (7°C), which is perfect for early spring planting. Plan to sow two to four weeks before the last spring frost in your area. For a fall crop, sow seeds in late summer so the plants mature in cool fall weather. Thankfully lettuce doesn’t mind a little frost. Some say it makes the leaves sweeter! However, a hard freeze below 25°F (-4°C) will kill the crop. Depending on the variety, you can harvest in as few as thirty days from sowing.
Lettuce can be grown in the GreenStalk Original Vertical Planter. However, small plants like lettuce are ideal in the shallower tiers of the GreenStalk Leaf Vertical Planter and it has more pockets per square foot. Head lettuces are best grown one per pocket and loose-leaf lettuces can be grown three per pocket. Baby greens or microgreens can be sown generously and there’s no need to thin them.
Watering & Fertilizing
Consistently moist soil is best for growing lettuce. Check the soil regularly and water as needed. If you began with a good quality potting mix with added fertilizer, you shouldn’t need to fertilize much more. If you feel your plants could use a little boost, or find the leaves yellowing, try a fish emulsion fertilizer. It might be smelly at first but the smell will pass in a day or two.
A note on bolting
Gardeners tend to have a whole language that feels a little intimidating if you aren’t familiar with the terms. Bolting is what happens when lettuce starts to grow a strong center stem and thick growth up through the center of the plant. This is inevitable as the weather warms. Flowers will grow at the top and if you like to save your seeds, get ready. There will be plenty! You may need to stake or support the plant if you want to try this. However, once a lettuce plant begins to bolt, the leaves will grow increasingly bitter. Bolting also happens with some brassicas and herbs.
Harvest & Storage
Lettuce is a cut-and-come-again crop that gives a continuous fresh harvest. For non-heading or loose-leaf lettuce, harvest when the outer leaves reach three to six inches. You can take several outer leaves from around the plant leaving the smaller inner leaves. They will continue to grow until you harvest again. To harvest a head of lettuce, make a clean cut with a sharp knife one to two inches above the soil line. The regrowth may not look the same as the original head, but you’ll still get some nice leaves! Whatever variety you’re growing, harvest in the morning when the leaves are cool and crisp.
It's not necessary to rinse lettuce before storage but it might be helpful in case you harvested a few little hitchhikers who also enjoy salad greens, like stray slugs or aphids! Dry completely with a salad spinner or lint-free cloth. Store lettuce in a loose plastic bag in the refrigerator for up to ten days.
One more thought
Because lettuce is a fast-growing plant with as few as thirty days to harvest, and because it grows bitter after second or third harvests, consider succession planting. One of our friends made a great video about it here!
We have a lot of fun growing fresh lettuce and hope you’ll try it too! For more information about growing in your specific climate, check out your local extension office. We’re here to help you grow — just email us at support@greenstalkgarden.com.
Happy gardening!
