1. Generally, you're told to plant lettuce seeds far enough apart for the plant to fully mature, but most gardeners prefer planting them much closer together because they enjoy harvesting the leaves when they are young and tender. Plant your lettuce in small spaces, in-between flowers, even in containers. Lettuce grows great in many locations and doesn't mind being shaded a little bit.
2. We recommend sowing new lettuce seeds every 30 days, that way you'll have a few new heads to harvest each month.
3. When harvesting, pick from the lower leaves first. They are the most mature.
4. Lettuce can be harvested at any size really. The smaller the leaf, the more tender and mild the leaf will be. If you're looking for more robust flavor, especially with the mustard greens, wait until they are large and fully matured. Most mustard leaves can reach 8" long.
5. If you're harvesting a lot of lettuce at one time, try to do it during the coolest part of the day. It will help keep the lettuce from wilting as quickly.
6. Speaking of wilted lettuce... we've all had it. We harvest a beautiful head of lettuce and then a few days later we look in the fridge and it's ends are wilted and it seems to look less than appetizing. There's an easy fix to "less than firm and crunchy" lettuce. Wash your sink out, then fill with ice and water. Submerge your wilted lettuce in the ice bath for 2-5 minutes and the lettuce will become crisp as it was the moment you harvested it.
7. When storing your lettuce, keep it sealed in an airtight container, with a damp paper-towel. You should easily get 2 weeks from your lettuce if you store it like this. You can even wash and chop your lettuce, then store as above for a "quick" and "easy" meal.
Have you sowed any lettuce seeds this month? Remember, plant lettuce seeds every 30 days for a continual harvest.