Do you grow lettuce? Have you had any trouble with your plants either drying out, bolting, not growing or succumbing to downy mildew?
Lettuce has certain growing requirements. When followed accordingly, it will produce fresh salad greens for months, from the spring through to fall.
In this post, I discuss what your lettuce plants need to grow well. I cover the right way to plant them, along with watering, harvesting and storing techniques.
What do salad greens need to grow well?
Lettuce does not like having its feet wet, meaning the plant’s roots don’t like to sit in wet, soggy soil. Be sure the soil is free draining. If it isn’t, mix in some peat or compost.
If growing in a container, choose a free-draining general purpose growing medium, like Seed Starting Mix. The medium should contain a mixture of peat moss, perlite or vermiculite. Worm castings may be mixed in for added nutrients.
When growing lettuce in the garden, choose a sunny or partially sunny location. Since lettuce prefers to grow in cooler conditions, choose a shadier location if your summers are hot and dry. The shade of a taller plant, a partially shady corner or a shade cloth will help to extend your lettuce growing season.
Ensure the soil is free draining. If your soil is clay-based, amend with compost, straw or vermiculite. If you have sandy soil, it will drain quickly. Amend your soil with compost to improve water-holding capacity.
When choosing fertilizer, select one with a higher nitrogen value. This is the first number of the N-P-K ratio. Nitrogen encourages leafy growth production. Compost is also a good choice for all vegetables. Alternatively, an organic all-purpose fertilizer or chicken manure pellets may be sprinkled on the surface of the soil.
How to plant lettuce
5 Steps for Planting Lettuce in the Garden:
- Select a full sun or partially sunny location of the garden. As mentioned above, be sure to grow in the shade of a taller plant, or set up a shade cloth to cover your seedlings during the hottest stretch of summer.
- If your soil is dry, be sure to water it well before planting.
- Plant your lettuce seedlings at a minimum distance of 6-inches apart.
- Firm your seedlings into the soil, to ensure proper root to soil contact.
- Water gently from above.
If Sowing Lettuce Directly in the Garden
Following the above 5 steps, sow your lettuce seedlings at a depth of 1/4 inch below the soil surface. Space them at a distance of 4 to 6 inches if your goal is to produce head lettuce. I recommend moistening the soil before planting, then watering again after planting with a gentle stream.
If your goal is to grow “Cut and Come Again” lettuce, space your seeds closer together in a furrow or scatter them over your planting area. Then snip baby leaves as they emerge.
Growing Lettuce in a Container
The Tools for Container-Grown Lettuce:
- Choose any shape container, as long as it’s a minimum of 12-inches in diameter. A window box container would also make a good choice. Depth isn’t a priority as lettuce has shallow roots.
- Newspaper or coffee filters to line your containers.
- Seed Starting Mix or general purpose potting mix.
- A nitrogen-rich fertilizer
- Lettuce seeds or seedlings
- Plant tags
10 Steps for Planting Lettuce in a Container:
- Line your pot with newspaper or a coffee filter, to prevent soil from spilling out of the drainage holes.
- Fill the pots with soil until the top 2 inches of the container.
- Sprinkle a 1-inch layer of vermiculite over the soil.
- Sprinkle 2 tablespoons of fertilizer over the soil and stir everything in evenly.
- Gently water the surface of the soil, to moisten the potting medium.
- Plant your seedlings in the container by making small holes in the soil.
- Firm your seedlings into the soil, to ensure proper root to soil contact.
- Pop in a plant tag next to each seedling.
- Water your container by either setting it into a basin or sink filled with water or give a gentle watering from above.
- Set in a full sun or partially sunny location.
The Right Way to Water?
Lettuce consists mostly of water. If left to dry out, the plant’s cells will dry as well, affecting healthy growth. In addition, hot temperatures along with dry soil conditions will encourage your lettuce plants to bolt, by producing a flower head. When this happens, lettuce becomes bitter and loses its tender texture and sweet flavour.
The opposite happens when the soil receives too much water. Poor drainage and saturated soil will cause the plant’s cells to become waterlogged, increasing humidity at the soil line. Too much water and damp conditions may lead to root rot or downy mildew.
Lettuce grows best when it receives even moisture. In order to provide your lettuce plants with even moisture, ensure the soil receives a minimum of 2-inches of water per week. The soil should be allowed to drain and dry slightly before watering again. If conditions are rainy, then it is best to water less. Adjust the amount of watering according to the season and temperature.
Container grown lettuce requires more water than garden grown lettuce. Since the soil in a container is shallow, it will dry quickly. Also, the walls of the container heat up quickly during the hot days of summer and will dry the soil much faster than garden soil. Water containers daily, at least once or twice per day, depending on the outside temperature.[et_bloom_inline optin_id=”optin_3″]
Finally, to check that your soil has received enough water, do a finger test! Push your finger into the soil to the depth of your second knuckle, or 2-inches deep. If you feel moisture at the tip of your finger, the soil has received enough water. If the soil feels dry, give it another drink and check again. Over time, you will easily recognize when the soil has been sufficiently watered.
Container vs. Garden
|Set container in a basin or tub of water to absorb water from beneath. This prevents a humid or damp environment when watering from below.||Water less if raining frequently, or ground isn’t free draining.|
|Allow water to absorb evenly.||Water daily if there’s a lack of rain or the soil dries quickly.|
|Use a watering can or watering wand and water gently, aiming for the soil line.||In normal conditions, give the soil a deep soaking at least 1 to 2 times per week.|
|Carefully lift container to test heaviness. If well watered, will be heavy. If light, water again.||Lettuce needs water to grow well. Be sure to provide adequate water to sustain healthy growth.|
How to Harvest Lettuce the right way?
Smaller, interior leaves grow quickly, while the larger, outer leaves grow at a slower pace. When harvesting lettuce, remove the outer leaves, leaving the interior smaller leaves to grow and fill out. In addition, regular harvesting of the outer leaves will keep your lettuce plants compact, allowing for closer spacing when planting.
I don’t recommend cutting your lettuce plants across the base, as that action will significantly reduce growth and productivity. However, if you’re growing for head lettuce, then cut your lettuce at the base, directly above the roots. Then either replace that lettuce head with a new lettuce seedling, or plant something different.
Finally, be sure to remove any damaged or yellowing, faded leaves. They are finished growing and will only pull energy from the plant. Damaged leaves also attract slugs and snails. To stop them from damaging your lettuce plants, be diligent about maintaining garden hygiene.
The Correct Way to Store Lettuce
After bringing your harvested lettuce leaves indoors, soak them in very cold water to replenish moisture loss. This will ensure that the leaves remain crispy and perk up if they began to wilt.
Check out my post, “1 Simple Tip for Cleaning Salad Greens” for lettuce cleaning and storing tips.
I have successfully been growing lettuce for many years and it is a mainstay in our home. By practicing succession planting throughout the growing season, it has allowed us to harvest lettuce from April to the first hard frost. I have found success with these growing techniques and I hope you too will find success growing your own lettuce and salad greens.