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When to Harvest Lettuce? Size Matters!

The satisfying crunch and fresh taste of biting into lettuce, especially when it’s placed in a delicious burger is an experience unlike any other. This plant is also commonly used in salads as well, and another interesting method of cooking this plant is you can actually grill it. Not only is this fresh green vegetable very tasty, but it is also extremely healthy.

Enriched with calcium, potassium, vitamin C and folate, and high water content- it is super hydrating and is a great addition to your diet. In fact, it is considered a superfood when it comes to weight loss. This plant is the most popular ingredient for salads in the United States.

Growing lettuce at home is better than store-bought ones because of the higher nutritional content and superior taste. An ideal vegetable for your garden, it is a cool-season crop which thrives best in spring and fall in most areas with temperatures between 60 to 70 degrees. Plus, you don’t have to wait long for you to experience this healthy and delicious vegetable. You won’t ever regret planting this in your garden. There are a few ways you can grow this crispy vegetable, and you must know how and when to harvest lettuce.

Growing Lettuce from Seed

Growing lettuce from seed is a perfectly ideal method. It is also very easy as they are small and need little depth.

A few weeks before the last frost date in your area, start the lettuce seedlings indoors in peat pots. These first few weeks are much needed time for the seeds to germinate and sprout before the ground outside gets soft enough for planting.

You need at least ½ inch of soilless growing medium in your pot for the seedlings to germinate much more effectively. Moisten the medium before sowing the seeds into the pot. You don’t have to ponder much about the spacing of the seeds as they will be transferred to the ground later on. Simply gently push the seeds into the medium when planting it into the pot.

The seedlings will need adequate sunlight, or alternatively artificial light until you can move them into the garden. Place your seedling near a window or any place that sunlight reaches inside. Make sure to keep the medium moist at all times, because failing to keep it moist will instead stop the lettuce from sprouting instead. However, make sure also to not overwater it as it can get saturated with water and causing a halt to sprouting. As soon as the soil can be worked with, you can transplant it outside. The time usually for the ground to get soft is 2 weeks before the last spring frost date.

You can simply sow lettuce seeds in the garden. Make sure you sow them ¼ inches deep, push them down, and water them. Based on the variety you choose and its directions, you will have to space the seeds accordingly. Typically, you can plant up to 10 seeds per foot. Some varieties may need at least a square foot of space whereas small varieties may take very little.

Alternatively, if you had prepared your seeds beforehand and they have already sprouted, then you can simply plant them into your garden. Dig holes in your garden and space them apart for 16 inches, the holes need to be just deep enough to accommodate the roots. Next, pick up the lettuce sprouts from the pots and place them into the holes. After this, plant the lettuce sprouts in a way that they stay upright by gently covering the roots with soil. Plant the sprouts in the same depth as they were once planted in the medium within those pots. Finally, water the lettuce sprouts after planting it.

When maintaining the health of your lettuce, you may want to consider these tips first. Use a watering can or a hose with a spray nozzle when watering your lettuce. By doing so, you avoid overwatering the lettuce and just making sure that the soil is always moist. Also after transplanting your lettuce, use some nitrogen fertilizer to encourage fast and strong growth.

The temperature required for seeds to germinate in the soil is at least 80 degrees F or warmer. In fact, hard lettuce is mostly grown indoors in warm weather during fall.

Growing Lettuce in Containers

When short on space, growing lettuce in containers is very common. This actually has several advantages. You have better control over the plant and can keep it safe from pests and insects which this plant is known for being troubled by. One other plus is that you can easily access the plant whenever you need some fresh lettuce leaves.

The right pot or medium is an important requirement when growing lettuce in pots or containers. 6 to 12-inch pots can be used to grow lettuce varieties. The container should have enough drainage holes. Clay pots are ideal because of their permeable material.  The plant also needs regular moisture but won’t tolerate too much of it- try not to wet the roots.

When it comes to sowing, you can either directly sow seeds or transplant them. Before planting, you should add ½ tablespoon of time-release fertilizer per gallon (of soil). The soil mix for lettuce growing in containers must have essential nutrients while also holding water. Peat or compost mixed with perlite or vermiculite works fine.

Water is a very important resource for lettuce grown using this medium. They need consistent but shallow watering. And lettuce grown in containers requires more water than the one in gardens.

Black Seeded Thompson and red or green oak leaf varieties are mostly recommended if you’re growing in containers.

When to Harvest Lettuce

The ideal time to grow lettuce is in spring or fall, in a spot with the full sun with cool, loose soil that drains well. Adding organic material and compost provides essential nutrients and improves its growing conditions. A pH of at least 6.0 is also required.

But the real question is how long does lettuce take to grow? Most lettuce varieties are ready for harvest about 30 to 70 days after planting them. You will know when to harvest lettuce when they reach their full size, but before they have matured. This is because young, tender leaves are better, tastier, and crispier. Harvesting lettuce in the morning provides you the best flavor and also by doing so makes the lettuce much more crispy.

You can also simply harvest lettuce leaves once they have appeared and are about 4 inches long. You can just snip the single outer leaves or remove a bunch of them using scissors. But you must not cut into or under the crown because then the plant will die. As soon as the lettuce matures though, you will want to harvest the entire plant as they will go bad if left for a long time.

One more point to remember is to harvest before the plant bolts i.e. form a seed stalk. After picking, lettuce can easily be stored for 1-2 weeks. 

Lettuce Bolting

Lettuce bolting is a common issue faced by many vegetable gardeners. It may be confusing when it happens but there are ways to prevent it. Bolting simply means that the plant has gone to seed and has produced flowers. The problem with bolting when it occurs in vegetables grown for their leaves is that they turn bitter. The leaves also become smaller and too tough.

The main reason for lettuce bolting is very warm temperatures. Heat becomes an issue especially the plant is about to mature. Dryness can also cause lettuce to bolt. And even too much cold can be a problem.

The best thing you can do to prevent bolting is to care for the plant and provide it the optimal temperature. Some varieties are sold with the ‘slow to bolt’ label, which you can definitely try. Crisphead lettuce variety is considered to be quite resistant to bolting. For head lettuce like iceberg, you should try planting it in the fall so the weather is cool by the time it matures.


Lettuce growing may seem tricky but it is really is not. All you need to know is how to provide the plant with ideal conditions and understand when to harvest lettuce so it is at its peak when you do. 

Once you have your fresh lettuce growing at home, there’s no limit to how you can enjoy its’ crispiness and flavor. You can add fresh, raw lettuce to salads for an extra punch and crunch. You can even grill or cook your lettuce and use it in many recipes. Lettuce juice and smoothies are another way to enjoy the nutrition and flavor together. 

Enjoy your fresh, tasty greens!

Now that you have learned how to grow and harvest some lettuce, do you have any thoughts or tips you would like to share? Do you have any questions perhaps? Comment below! Also, our website offers other guides as well such as How to Prune Desert Rose and How to Prune Dill.

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