How to Grow Lettuce
Lettuce is must-have in the garden. There are many types of lettuce, and they vary in taste, look, growing time, and growing season. Harvesting lettuce fresh from the garden for a salad is the ultimate in fresh farm-to-table eating. Lettuce has a short growth time and can be planted multiple times throughout the season. Growing lettuce is one of the many joys of having a garden!
Types of Lettuce
There are four main types of lettuce: Leaf, butterhead, romaine, and iceberg lettuce. You can find our lettuce seeds here.
The most popular among gardeners, leaf lettuce has three subcategories: red, green, and oak. All types grow individual leaf stalks for harvesting, hence the name. Because the leaves are single, they can be harvested as needed without disrupting the entire plant—this is great because leaf lettuce is very perishable and should be picked right before being served for the best quality. This type is the easiest to grow.
Butterhead, or Round
Butterhead lettuce has a loosely shaped head with soft and tender dark green leaves. There are two varieties of butterhead: Bibb and Boston. They are both light yellowish green and buttery in appearance and taste.
Romaine lettuce grows in a tall, dense, tightly packed, oval-shaped heads and is super crunchy. It is favoured for its texture and heartiness.
Light green leaves tightly compact around the head of this bowling ball-shaped lettuce. Its flavour is very mild, and some say virtually non-existent. The benefit of this variety is that it can be stored for a long time. Iceberg lettuce is the most difficult lettuce to grow and shouldn’t be started from seeds. Purchase starts from a garden center for the best results.
How To Grow Lettuce
Growing lettuce is so much fun because there are so many options. It can be planted in successive sessions over weeks and months so you can have lettuce all season long. Lettuce can be grown in the outside garden, in greenhouses, and indoors. Plus, because of the varieties, you could grow 8-10 types per year if you start a new type with each planting.
Lettuce doesn’t transplant well, so it is best planted in the place it will stay, wherever that may be; if you are planting outdoors, plant in the spring as soon as the ground can be worked. In general, lettuce prefers cool weather, and the seeds will not germinate in temperatures above 35C with15-21C being their preferred temperature. Temperatures above this will result in bitter leaves and stunted growth. Although you will see when you start exploring seed types that there are many nowadays that are being developed to withstand warmer temperatures.
Step One – Plant Seeds
Lettuce seeds are teeny tiny, and it is easiest to spread them over an area and then thin them out once they sprout—plant in full sun when the temperature is cooler. The seeds can be spread over sections or in rows. Aim for 10-20 seeds per foot. If planting in rows, space them 10-12″ apart. Lettuce seed varieties can be combined and then spread out for planting—this is a fun way to add more colour and variety to the garden! Lightly cover the seeds with 1/4″-1/2″ of soil. The ideal soil pH is between 6.0-7.0.
Step Two – Daily Care
Water the seeds carefully each day until they sprout. Once the seedlings reach 2″ tall, they can be thinned. 6-8″ apart is usually good. If they aren’t thinned, they will overcrowd each other and none will grow well.
Once they sprout, frequent light watering is best. The root systems are not deep, and the plants can be disturbed easily. Over-watering can lead to root rot and leaf diseases. When weeding, use caution too so as not to disrupt the roots. Keeping weeds away is super important since the lettuce seedlings are so small and fragile, and any competition for resources can cause them to fail.
Step Three – Plant More Lettuce!
To keep a steady supply of fresh lettuce, plant more sections or rows every 10-14 days. Because lettuce doesn’t do well in the summer heat, once the temperatures start to rise, plant the seeds in a cool greenhouse or partially shaded space. They need light, but excessive heat or humidity will slay them. Or, use varieties that are made for warmer temperatures. Once the weather starts to cool again, you can go back to planting them outdoors.
For indoor growing, the temperature needs to be between 12-24C, and the plants need 8-10 hours of light per day.
Step Four – Harvesting Lettuce
The harvesting of lettuce varies depending on the type. Leaf lettuce is ready for harvest as soon as the leaves reach 5-6 inches long. Remove the outer stalks first by carefully snapping them off or using scissors to cut them. New leaves will grow over a period of several weeks as long as you continuously harvest them.
Butterhead is ready to be harvested when the leaves cup inwards and form a loosehead. Cut the entire head off at the base and use it as soon as possible. Romaine lettuce will grow long, overlapping leaves around 6-8 inches tall (or higher) and form a tight head. To harvest, take off individual leaves or cut the entire head off at the base. Iceberg lettuce forms a tight, round, dense head, and at harvest, the entire head should be cut at the base.
If you ever see tall stalks appearing in the center of your lettuce plants, harvest them immediately. The plants have gone to seed, and the leaves will very quickly become bitter and inedible.
How to Store Lettuce
When storing lettuce in the fridge, keep them away from bananas, pears, and apples. These fruits produce a natural ripening agent that will make lettuce wilt quickly and go bad.
Growing lettuce at home is incredibly easy, and it’s the freshest and tastiest way to get it! If you have any tips on how to grow lettuce, please feel free to share it with us in the comment section below.