As a cool-weather crop, lettuce germination time is the shortest in the spring and fall. Lettuce seeds can germinate at temperatures as little as 40 degrees Fahrenheit.
However, the ideal temperature for germination and growth is somewhere between 60- and 65 degrees Fahrenheit. (16 to 18 C).
So how can lettuce seeds grow more quickly? One trick to reduce lettuce germination time is to soak the seeds for 12 to 24 hours before sowing to hasten their germination.
Additionally, keep the soil cool and expose them to lots of light from the beginning.
Lettuce seeds will germinate in 7 to 10 days, depending on the type, in ideal growing conditions.
Although loose-head varieties have a chance to sprout more quickly than heading varieties, all seeds require the same combination of soil, moisture, and light to encourage germination.
Read Also: Iceberg Lettuce Growing Stages
When to sow lettuce seeds to reduce lettuce germination time
How to decide when to sow lettuce depends on when you want to harvest:
- For crops in the summer or fall, you should sow seeds outside from the end of March to the end of July.
- For an even earlier harvest, sow seeds indoors in seed trays at the beginning of February and plant them outside at the beginning of March under cloches or plastic tunnels.
Most people like to plant a few seeds every two weeks so there is always lettuce in the garden that is ready to pick.
This keeps you from having a lot of stuff ready at once and then nothing.
Keep reading for more tips to reduce lettuce germination time.
You might also like: Perfect Soil Mix Recipe For Raised Bed Gardening
Do lettuce seeds need sunlight to germinate
Even though it grows best in full sun, lettuce is one of the few plants that can handle a little shade.
In fact, as the weather gets warmer, spring crops often last longer if they are kept out of the afternoon sun. Even in a small space, like a pot, you can grow a lot of lettuce.
For lettuce seeds to grow, they need a lot of light. Like most seeds that can’t grow without sun, lettuce seeds do best when they get 12 to 16 hours of sun every day.
Indoors, put the seed containers in a sunny, south-facing window and turn them a quarter turn every day.
This will keep the seedlings from reaching too far for the light and making their stems weak and long.
Depending on the type of lettuce seed, it can start to grow when the soil is between 35- and 80 degrees Fahrenheit.
But for germination, the best soil temperature is between 70 and 75 degrees Fahrenheit. When it’s cooler, it takes longer for seeds to grow.
When it’s hotter than 70 to 75 F, lettuce seeds might not grow. You might think that lettuce seeds will grow faster in the dark because they like shade.
Read More About Preparing A Garden Bed For Vegetables.
Will lettuce seeds germinate in the dark?
Lettuce seeds need light in order to grow. Lettuce seeds are what are called “photosensitive”. Another term used to describe them is “photodormant” meaning lettuce seeds won’t sprout in the dark.
After sprouting, lettuce seedlings need the same amount of exposure or time in the sun to grow a field of lettuce with heads that are all about the same size.
Most seeds grow better in the dark than they do in the light. Are you ready for a quick lesson in science? The carbonic acid gas in the seed breaks down when light hits it.
This lets the oxygen out and fixes the carbon. All the parts of the seed harden because of these three things, which makes it hard for the plant to grow.
Sow Lettuce Seeds In Fine Soil
Lettuce seeds can grow almost anywhere you plant a seed. However, 2 problems will come up.
First, lettuce seedlings are weak. They are easy targets for pests that love to eat their tiny leaves.
Secondly, diseases might kill them before they get to maturity. When you use fine potting soil instead, you can avoid this.
Plant the lettuce seeds shallow and cover them lightly. Too deep and they won’t be able to come out of the soil because lettuce seeds need light to germinate.
Before sowing, fill your tray or container with potting soil from a garden supply store rather than soil from your backyard.
Water them very gently once you’ve planted the seeds. They will emerge in about a week if you keep them damp, but not dripping wet.
Lettuce Varieties
One can cultivate and enjoy a wide variety of lettuces: Iceberg, romaine, leaf, butterhead, bibb, crisphead, red leaf, green leaf, and stem lettuce are all available.
It’s clear from the names what each category is meant to represent. Butterhead lettuce, iceberg lettuce, and romaine lettuce are just a few examples.
Although there are subtle differences across the varieties, they all have a common ancestry.
For example, sowing romaine lettuce seeds inside about 10-12 weeks before the final projected spring frost increases the likelihood of a successful crop.
4–6 weeks after seeding, the seedlings are ready to be transplanted into the garden.
The seedlings planted in late February will be ready to be transplanted into the garden by the beginning of to the middle of April.
To get the best romaine lettuce germination time, the seeds should be kept damp for 14-16 hours a day, and the grow lamps should be held no more than a few inches over the plants’ foliage.
You might also like these posts about growing other vegetables:
How To Grow Cucumbers In Pots: When, Where, And How Of Growing Cucumbers In Pots
Growing Zucchini In Pots: When and How to Grow Zucchini In A Pot
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