Almost all lettuce varieties and most greens are cool-season plants. This means they thrive when the average temperature is below 70 degrees.
Choosing a shallower, longer pot will give you more surface area, which means room to grow more plants.
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Lettuce is 95% water, which means it requires near-constant access to moisture to avoid wilting. At the same time, it does not do well in standing water.
There are plenty of lettuce and greens varieties to choose from. Some are better suited to the restricted growth conditions of containers than others.
Most greens and lettuces do best when sowed directly into the pot they will be grown in.
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