Time to Sow Lettuces

Early April is the time we start thinking about sowing our first lettuces for outside transplanting. Despite the odd weather –we have had more snow here in the past few days than in January and February combined!– we are sowing and pricking out now in the hoop house for our spring outside-planted lettuces. In the greenhouses, lettuce season is already well under way, but for the first lettuces that will be planted outside in the garden, now is the time to start those seedlings. As the warmer weather comes in May, we love to load up our salad bowls with all the diverse colors, textures and shapes that our buttery, tender, crisp and sweet lettuces comes in!

Starting seeds indoors gives you a great jump on the season, but you need to pay attention to a few key things: Light, temperature and moisture.

Lettuces, like all indoor-sown starts, will need as much light as you can get for them. Sunny windows work just fine, but on any days that warm up above 50F, you can also put your lettuces outside for extra light. Grow lights help too, but outdoor light is the very best for plants, as long as the temperature is warm enough, and they are kept out of the wind. The more you can bring your seedlings outside, the stronger and less leggy they will be. Strong seedlings make healthy, strong plants. Lettuce seeds like some light when germinating, so only lightly cover them with soil, so you can still see the seeds.

Lettuces don’t want the hot temperatures that your eggplant and pepper seedlings love, so if you have a cooler, but still very sunny windowsill, that’s best.

Lettuces, like most seedlings, like good even moisture, but don’t like to be soggy, or they will become susceptible to diseases such as damping-off.

We generally sow our lettuce seeds fairly thickly  (see the picture above) in lines in a tray, then “prick” them out (transplant them) to give them more room once they have germinated. To prick out lettuces, gently loosen the seedlings from underneath with a wooden seed label, the handle of a spoon or a Popsicle stick. Take one seedling at a time and move it to a new home in another container or flat. If you prick them out before the first true leaves appear, the lettuce seedlings will be small and a little fiddly to handle, but the root system will be easier to work with, as each seedling will only have one single rootling. Lettuces like their roots to go straight down, so make sure you poke a good hole for the transplants, but you can also trim off the roots so that there is about 1 inch left on the seedling, as more roots will begin to grow right away. Also, lettuces like to be planted with the soil at the same level as they have been growing–they don’t like to get soil too far up on their stems or between their leaves, as this can cause disease problems. Handle delicate lettuce seedlings very gently by the leaves rather than the stems–lettuces will grow lots more leaves, but they only get one stem, so if it gets damaged, that sets back or can even kill the plant. Gently but firmly tamp down the soil around each seedling as you plant it. We generally give each lettuce seedling about 2 inches of space on each side when we prick them out, so that they have some room to grow, but also so that we can fit plenty into a tray. When they’ve been pricked out, the lettuces will be happy in their trays, given adequate light, not too much warmth, and a steady but not soggy amount of moisture until the end of April or early May when it will be time to plant them outside in a well-prepared garden bed.

Lettuces don’t need a lot of compost, so if there is an area that got some last year, perhaps where you had grown squashes, tomatoes or cabbages, that spot should do just fine for lettuces without additional compost.

For a steady supply of lettuce throughout the spring, summer and fall, we plant many different varieties, some are best suited to the cool spring and fall months, some can stand up to more heat. Read the descriptions to make sure you’re getting what you need for your garden plans. Also, we sow in succession so that we always have fresh lettuce coming along, since when lettuce starts to get old and bolt (send up a stalk) it can get bitter. This means that about every three weeks, we sow some more lettuces. Lettuces grow fairly quickly, and since we like to salads nearly every day (sometimes twice!) we plan on sowing enough for a two to three week period. For a small household this may mean only a few lettuces, or for a larger garden that feeds many this may mean many. Think about your salad needs and wishes, and sow for those!