This is another installment about growing vegetables in containers. Click on Gardening Tutorials to see more in the series.
One of my goals is to grow as much fresh food as possible year round. In winter, it is nice to have an assortment of greens available to complement things from the cellar, pantry or freezer. Cold frames help make that possible, and so does growing salad greens in containers in the greenhouse. But there are many advantages to growing lettuce and other greens in containers in any season, outdoors or inside.
For one thing, containers can definitely help those with critter problems like munching rabbits. Just put the containers on a table or somewhere high enough where rabbits can’t reach. And for those with bird or deer problems, the containers can be covered with netting.
It’s also easy to deal with containers when it comes to planting and harvesting. And there’s no need to bend over to thin or weed either! Most greens are shallow rooted, and ideal for growing in containers. I use a good quality potting mix for soil, enriched with either a little compost or some organic fertilizer. I also occasionally give the containers a drink of some half-strength liquid fertilizer. Of course the containers will also need to be watered regularly.
There’s no need to spend a lot of money on the container. Anything that is at least 4-6 inches deep will work for salad greens. I like to use inexpensive plastic windowbox planters. Do make sure the container has drainage holes.
Right now in the greenhouse I have several containers of salad greens growing. I planted this round container with some young seedlings I had left over at transplanting time. It’s got a mix of several lettuces plus arugula, pac choi and tatsoi. I spaced the seedlings about 2 inches apart.
About 6 weeks later, they had grown to fill the pot and were ready for harvesting.
For these greens I used a cut-and-come-again method of harvest, cutting the greens with scissors about 2-3 inches from the soil line. That way, the growing point of each plant is still intact and the greens will regrow fairly quickly. Renee’s Garden has a great article on growing and harvesting mesclun mixes.
There were just enough greens from this cutting for my wife and I to have a nice sized salad for lunch. There’s nothing like fresh salad greens that you’ve grown yourself!
I have other containers planted with lettuce mixes, plus some with arugula, and even one with onions for scallions. These can also be harvested a leaf at a time, or cut at the soil line and allowed to regrow. I planted the containers in the photo below with mixed lettuce seed. Lettuce mixes are available in most seed catalogs, or you can make your own from seed you have on hand. For these I just sprinkled the seed on top of the soil without even covering it. The lettuce germinated in less than a week. Just follow the package directions for whatever seed you are planting.
I cut the lettuce with a pair of scissors just like I did the mesclun mix, about 2-3 inches above the soil line.
Greens can also be grown indoors under lights, and containers are an excellent way to do that. You can even get an early jump on spring by starting greens indoors, then moving the containers outside when the weather warms up a bit.
There’s a wide variety of greens that will do well in containers, including (but not limited to) lettuce, spinach, endive, beet greens, arugula, purslane, kale and mustard. There are also many Asian greens like pac choi, tatsoi, komatsuna and mizuna that work well.
If you’ve never tried growing salad greens in containers, give it a try! You can grow the ones you like to eat, and for a small investment of time and materials, have them fresh when you want them.