How to Grow: Lettuce is a cool-weather crop that thrives in the temperature range 60-65 degrees F, and if thoroughly hardened, most varieties survive temperatures as low as 20 degrees F. Cold-adapted varieties survive much lower temperatures.
When can lettuce seedlings be planted outside?
Lettuce loves cool weather. You can begin planting leaf, romaine and butterhead lettuce as soon as the soil can be worked in the spring. Depending on the variety, lettuce germinates in temperatures between 40 to 85 degrees F.
What temperature should lettuce seedlings be?
Lettuce can tolerate a few days of temperatures from 80 to 85°F, provided that nights are cool. Lettuce seed will germinate at 35°F, but optimum germination is 70 to 75°F.
Should I cover my lettuce?
Lettuce is tolerant of cold temperatures for short periods of time, although growth will slow down. To protect lettuce in frost-prone areas, plant romaine or butterhead lettuce, which are the most cold-tolerant. When frost is predicted, cover the garden with sheets or towels to provide some protection.
At what temperature should I cover my lettuce?
Unless you are facing deep frosts, you don’t even need to protect lettuce in cold weather. However, if your temperatures are consistently just above freezing, you can use a row cover or clear garden plastic sheeting to raise the ambient temperature and increase their growth rate.
Can lettuce be planted before last frost?
Most cool season crops, like cabbage, broccoli, lettuce and many others, can tolerate a light frost and will grow best when sown a couple weeks before your last spring frost. Some, like peas and spinach, are so cold-hardy they can even be planted “as soon as the ground can be worked,” as many seed packets say.
When should I start lettuce seeds indoors?
For a jumpstart on the spring garden, start lettuce seeds indoors 3 to 4 weeks before your area’s last hard frost — which is around 28 degrees overnight.
Why are my lettuce seedlings floppy?
Causes of Lettuce Damping Off
Too much moisture is the most common cause of damping off, as it makes seedlings much more susceptible to stem and root infections. Damping off is usually a sign that you are overwatering or that the humidity is too high. The youngest seedlings are the most vulnerable to damping off.
Does lettuce need a heat mat?
Lettuce germinates in cooler temps, around 65 to 68 degrees is optimal, so no heat mat needed. Also don’t burring the seeds, place them on top of the soil in the cell tray and lightly cover the seed. Lettuce is not a heavy feeder and, in most cases, does not need to be fertilized after the initials planting.
Why are my lettuce seeds not germinating?
Why won’t my lettuce seeds germinate? If your lettuce seeds don’t germinate, they are most likely old. Otherwise, you may have planted them too deep, or the soil is too warm, too wet, or too dry.
How often should lettuce be watered?
twice a week
Lettuce has shallow roots, so plants need consistent watering. Check at least twice a week and water if the soil is dry down to 1 inch deep. Containers of lettuce need to be watered more frequently than garden beds, especially in the summer.
Do you need to cover lettuce from frost?
Even these cold-hardy greens will need some extra protection if frequently exposed to temperatures in the low 20s and teens. You can protect your cool season crops (including lettuce, which is more easily injured than other greens), by throwing a blanket or row cover over the plants.
How much light do lettuce seedlings need?
As shown in the table, most leafy greens grow well with at least 5 hours of direct light per day. This means 5+ hours of sunlight hitting the plant leaves is recommended for growing lettuce and other leafy greens.
How do I protect my lettuce seedlings from frost?
HOW TO PROTECT PLANTS FROM FROST
- Lay a pane of glass, held up by small pots, over low-growing plants.
- Relocate outdoor potted plants somewhere warmer, such as on a verandah or under the house.
- Save old net curtains, bed sheets and shadecloth for emergency overnight protection.
Can seedlings survive frost?
Hardy and Semi-Hardy Crops
Hardy vegetables tolerate cold temperatures the best—their seeds will germinate in cool soil, and seedlings can typically survive heavy frost.
How do you grow lettuce indoors in the winter?
Bright grow lights or bright daylight window
If your natural light is dim in winter, provide supplemental lighting for baby greens. The full spectrum grow light should be placed about 4″ above the top of the leaves. I use lights to grow lettuce indoors in January, when the natural light is lacking.
When should I plant lettuce?
When to sow depends on when you want the harvest: For summer/autumn cropping: sow outdoors from late March to late July. For an even earlier crop, sow indoors in early February in seed trays and plant out in early March under cloches or plastic tunnels.
Can I grow lettuce in winter?
Varieties of winter-hardy lettuce can keep cropping during any mild spell in winter, then again from early spring. Winter lettuces are hardy, tenacious and tasty!
How cold can cabbage seedlings tolerate?
about 26 º F.
Cabbages can take cool temperatures down to about 26 º F. They are often planted later in the year for a fall harvest, but if you start them early enough, you can still get a crop before it gets too hot. A light frost improves the sweetness of cabbages.
What is the fastest way to germinate lettuce seeds?
Lettuce seeds don’t sprout easily when the soil temperature is over 22°C (72°F) in summer. Get around this by sprouting them indoors in a cool area, or pre-sprout by sprinkling seeds on a damp paper towel and placing it in a plastic bag in the fridge for a few days.
Can you fix leggy lettuce seedlings?
The best way to fix leggy seedlings is give them more light, ASAP! This could mean adding a supplemental grow light if you’re not using one already, upgrading to a stronger light, or lowering your current light closer to the seedlings so it is more effective.