Growing Lettuce: Your Complete Guide
One of my favorite crops to grow is lettuce. While I don’t spend much time discussing or showing it on my IG page, it is a staple in my garden during fall, winter, and early spring. Why? Because it is fast-growing and relatively pest and disease free. This article will discuss who should grow lettuce, when to plant, and tips for teaching you how to succeed.
When to grow lettuce
Like other leafy greens, lettuce does best in early spring or fall. That is because lettuce is a cool-season crop that produces best when temps are 50-70F. You can grow lettuce through the winter in places with mild winters, like Houston and southern California.
Can lettuce handle the heat?
While there are some heat-tolerant varieties, the term heat tolerant can be a little misleading. I have yet to find lettuce that can produce in these Houston summers. Lettuce, a member of the aster family, cannot withstand extreme heat. Lettuce can withstand a few days where the highs are above 80F as long as you have cool nights in the lower 60s. Any prolonged exposure to temperatures over 75F will cause the lettuce to bolt. When lettuce bolts, it stops producing edible leaves and focuses on flowering and producing seeds. The existing leaves become bitter, almost to the point of being inedible. If you notice your lettuce starting to bolt, harvest what you can and remove the spent plant.
Can lettuce handle the cold temps?
The most straightforward answer is yes. Mature lettuce plants, the keyword being mature, can withstand freezes. I have even had some lettuce survive through the infrequent but occasional hard freezes down here. The colder the temperatures and the longer the lettuce is exposed, the worse the damage will be. Frost damage affects the leaves, causing them to appear thin, dark, wilted, or discolored. If your lettuce is damaged in a freeze, cut off all the damaged leaves to signal to the plant that it is time to regrow.
It is also essential to plant your lettuce before the cold temperatures roll through. This is because cold temperatures below 50F cause lettuce to grow slowly.
Growing Lettuce: What else do you need to know
Sun Exposure
Lettuce grows best when it receives full sun. Almost all edible vegetables do. But lettuce, like other leafy greens, can grow well in partial shade, which is 4-6 hours of sunlight. Remember, sun exposure does not have to be consistent. In my garden, I always try to plant lettuce and other leafy greens where they receive morning sun and then shade in the afternoon.
Soil Conditions
Lettuce grows best in deep, well-drained soil. While I have successfully grown lettuce in sandy and clay soils, lettuce will not grow at all in acidic soils. So, please keep it away from your blueberries, azaleas, and roses. Before planting, make sure to work rich organic matter into the soil.
Since lettuce has such shallow roots, mulching will help to preserve the moisture. Mulch will help prevent the soil from drying out and regulate the soil temperature. Read more about the benefits of mulching here.
Fertilizer and Water
Lettuce requires regular watering. Make sure to keep the soil moist but not soggy. If possible, try installing an automated watering system to help limit the fluctuations in the amount of water.
Like all leafy greens, lettuce needs nitrogen. Nitrogen is the macronutrient that is responsible for lush green and vegetative growth. If you apply rich organic matter before planting, you usually will not need any extra fertilizer throughout the growing season. If you forget to add the organic matter before planting, then be prepared to use liquid fertilizers like fish emulsion, seaweed, or compost tea.
Growing Lettuce in Containers
No garden no problem. Lettuce grows well in containers. Since lettuce has such a shallow root system, the containers do not have to be deep. I have successfully grown leaf lettuce in a saucer that you would typically place underneath a container to catch runoff. You can even grow lettuce indoors if you can provide ample light. When selecting a container to grow lettuce, wider is better than deeper.
How long does growing lettuce take?
Lettuce is one of the fastest-maturing crops you can add to your garden. The short days to maturity make it perfect for short growing seasons, succession planting, and interplanting. On average, it takes 60 days for head lettuce to form, and leaf lettuces can begin harvesting in less than a month. This short growing time and how quickly you can get a harvest are why I believe all new gardeners should start by growing leaf lettuces.
Lettuce Spacing
Proper spacing is vital for all plants to grow correctly, including lettuce. Crowded plants usually lead to many issues- stunted growth, poor ventilation due to lack of airspace, competition for nutrients within the soil, and more.
Most lettuce that produces heads need a minimum of 6 inches between plants. I don’t have the best success growing head lettuce down here, so I prefer leaf lettuces. These can be planted much closer together, around 4 inches apart. This suits me better as an urban gardener who aims to maximize my yields within my limited space. If you are growing baby greens, then there is no need to pay attention to spacing. Scatter the seeds and let them do their thing.
If growing directly from seed, be prepared to thin your plants.
Pests
Out of all leafy greens, lettuce attracts fewer pests than kale and others. The most common pest that affects lettuce are – aphids, caterpillars, leafhoppers, cutworms, thrips, snails, slugs, and beetles. I spend more time dealing with larger pests like birds and rabbits than I do the insects. Why? Because I usually shield the new seedlings with a floating row cover.
How to Harvest Lettuce
Do you know what’s great about lettuce? You can harvest it at any time! If you are growing leaf lettuce, cut or pluck away young leaves. Since new growth sprouts from the top of the plant, it is best to harvest the lower outer leaves first. When harvesting, leave at least 40% of the leaves attached to the plant to aid photosynthesis. This is my preferred method and is known as cut and come again. With this method, I can harvest from the same plants for months unitl they begin to bolt, or my next round of lettuce plants are ready to go.
If you are planning on harvesting full heads, allow the plant to reach maturity before cutting it at the base about 1” above the soil.
Harvest lettuce in the morning when it is cool outside or late evening. Once harvested, wash and store it as quickly as possible. How do you store the lettuce? Keep reading to find out.
Storing Lettuce
If you’re anything like me, you harvest a couple of times a week and store the produce in the fridge until ready to eat. The best way to keep fresh lettuce is in an airtight glass container in your refrigerator. Lightly mist the leaves before placing a dry paper towel on the lettuce. This will help absorb excess moisture while delivering the necessary water to keep the leaves fresh and crispy.
Tips and Tricks: Growing Lettuce from seed
Lettuce is one of the easier plants to grow from seed. I refer to it as one of those set it and forget it plants. As long as my soil has the proper nutrients, I can usually throw some seeds in the garden, and besides thinning, there is minimal care.
Lettuce needs light to germinate, so if you start indoors, you will need proper lighting equipment or a bright windowsill. Without adequate lighting, the seedlings will become leggy.
Lettuce is an excellent season crop, so it prefers slightly cooler temperatures to germinate. Please do not use a seedling heating mat unless you live in Minnesota or Alaska, somewhere it is frigid.
Sow the lettuce seeds on top of the soil. I like to sprinkle my seeds on top of the soil and then come back with compost in my hand and lightly sprinkle about ¼“over the entire surface.
After sowing, make sure to keep the seeds moist.
Once lettuce has its first set of true leaves, asses the spacing between the seedlings and thin accordingly.
If you follow the information in this article, you will be able to grow an amazing harvest of your own. No fall garden is complete without lettuce.