To get to a full crisp head, some very distinct iceberg lettuce growing stages have to cross. It’s a magnificent but long transformation from seed to full head. It can be shorter if you know how to speed up germination and growth.
Iceberg lettuce is an annual crop. You can grow it in most regions. Because iceberg lettuce likes cool weather, growing them along the coast or in Mediterranean climates is challenging due to the hot weather.
In such cases, it’s better to wait for the cool months to start planting iceberg lettuce. That’s why you can easily regrow lettuce stumps in water.
Iceberg lettuce is a popular type of lettuce around the world and especially in the US. It is a common addition to salads because of its neutral taste which balances other biter lettuces.
Iceberg lettuce is also known as crisphead because it has a wound head of crisp light green leaves. You have the option of growing them from seeds or growing lettuce from stump remains.
Unlike butterhead lettuce which takes roughly 9 to 10 weeks to get to maturity, it takes 10 to 12 weeks for the iceberg lettuce plant to go through all iceberg lettuce growing stages.
Iceberg lettuce growing stages
1. Iceberg lettuce germination
The first of the iceberg lettuce growing stages is germination. Iceberg lettuce seeds only begin germination in the right conditions.
Iceberg lettuce seeds can germinate in cold soil (40 F) and soil as warm as (80 F). However, the ideal iceberg germination temperature is about 75 degrees Fahrenheit.
In case the soil or germinating media gets too cold, you can place a heating mat or pad under the germination container or tray. In dry weather, some misting can help keep the germination area moist.
Iceberg lettuce seeds germinate into roots and shoot. The shoot is made of 2 cotyledons or seed leaves which are the first leaves you see.
It takes about 7 to 21 days before you see the first leaves after planting the iceberg lettuce seed.
To continue with germination, read How You Can Reduce Lettuce Germination Time
2. Iceberg Lettuce Seedling Stage
After germination, seeds become seedlings. At the seedling iceberg growing stage, the roots appear followed by the shoot. The shoot has the first leaves also known as the seed leaves or cotyledons.
The first true leaves appear much later. If after the first true leaves appear is when you begin to see the rosette pattern take form.
Prepare your garden, pot, or raised bed as you wait for the seedlings to get to a height of about 3 to 4 inches tall. Makes holes about an inch deep and 5 to 6 inches apart.
You want to leave enough room for the base of the stalk to be above the soil line. Transplant the seedlings.
3. Forming The Lettuce Head
The lettuce leaves begin to develop into the head after the rosette stage. For a uniformly wet growing environment throughout the growing season, water lettuce is often watered.
Sprinkle 1 teaspoon of granular 10-10-10 fertilizer around the base of each plant three to four weeks after transplanting, and then water to hydrate the fertilizer.
Before spraying aphids with a strong stream of water, remove slugs and snails and look for aphid infestations on the underside of the leaves.
4. Lettuce Harvesting Stage
Iceberg lettuce is harvested whole including the roots. The right way is to uproot or cut the plant before it reaches its mature size. If left to mature, the lettuce will bolt.
The type of lettuce that is growing will determine when it should be harvested. The plants taste better if they are gathered in the morning, according to Gilmour.
Use a sharp knife or only a few leaves off the plant at a time to chop the lettuce heads off at the soil line. Lettuce is an annual that must be replaced from seed or seedlings because it won’t grow after the first season.
Iceberg lettuce growing challenges
Does lettuce regrow after cutting?
One common lettuce harvesting question is does lettuce regrow after cutting. The primary stem of lettuce can be cut or pulled off, and the leaves will then reappear. In as little as a week, lettuce will sprout new growth.
If the root was damaged or there are less than 1-2 inches of stem and leaves at the base, it will not regrow. The most common way of harvesting is to cut and come back.
However, you might not get a full head of lettuce after cutting or plucking. Iceberg lettuce is more suited for a single harvest.
Lettuce head bolting
According to almanac, mature iceberg lettuce begins to produce flowers and seeds which delays the formation of the lettuce head. It can delay the head formation by a month.
In addition, its leaves have a bitter taste and get stiff after the flowers and seeds appear. This phenomenon is called bolting. Bolting is brought on by conditions like high temperatures, longer daylight hours, and low humidity.
You can easily trim bolted lettuce with gardening shears or with a sharp knife, but since the lettuce will be bitter to eat, it’s best to just pull the plants out. You can then replant if it’s early enough in the season.
You’re probably wondering ‘can you reverse bolting?’ Only if you catch it early enough. It’s more like arresting it. You can do this b cutting off the flower and flower buds early on.
Iceberg lettuce not forming head
The response to why is your iceberg lettuce not forming a head goes like this: iceberg lettuces perform their best in the spring or fall because they prefer cool weather. Gardeners in warmer climates will frequently end up with lettuce harvests that don’t have any heads.