It’s the time of year when vegetable transplants (or “starts) begin to show up at nurseries, hardware and grocery stores, and plant sales. Transplants are wonderful for many reasons. First, certain crops are difficult to grow from seed and will simply perform better if transplanted. In order to grow to maturity, many summer crops need to be propagated indoors for several weeks while the weather is still too cold to plant outside. Most plants from professional greenhouses arrive healthy and viable, but they don’t always receive the care they need from the retailer. Vegetable plants grow quickly. When stuck in small nursery containers, they can use up all of the available soil nutrients and become so stressed that its hard for them to fully recover. Here are a few things to consider when buying vegetable transplants:
Bigger isn’t always better: You want transplants that are large enough that they are ready for outdoor planting (typically they should be showing at least 2 true leaves*), but not so large that they are discolored stressed or already starting to bolt*. I look for a supple quality in my transplants. Plants that have been potted up too long start to look tall and “leggy”, and the stems often look a little stiff. A vegetable transplant that is oversized for its nursery pot may have a hard time adjusting to the garden and setting out healthy roots.
Look for plants that have recently arrived at the nursery: You want dark green, healthy-looking plants. While some varieties are grown for their unique color (think red cabbage or purple kale), generally if the leaves have started to turn blue, purple, or yellow, they are probably not worth buying. Discoloration is a sign of nutrient deficiency. Keep in mind that, flowers are not necessarily a good thing: It’s enticing to pick out the tomato transplant that already has a set of flowers. Flowers equal fruit, right? Technically, yes, but flowers also signal that a plant believes it has reached maturity and is ready to reproduce. If you purchase an 8” tall tomato plant that is already spending energy on flower production, it may never reach its full size and potential. If allow those first flowers to set fruit, it’s likely the plant will be stunted and you may get 3 lovely little tomatoes this season. However, if you select a dark green, non-flowering tomato, and encourage lots of green vegetative growth before allowing it to set flowers, you’re likely to end up with tens or even hundreds of tomatoes from the same sized transplant. If you do find an otherwise healthy looking vegetable start that happens to have flowers, no worries, just be sure to pinch them off before planting!
Take a close look to and determine how many plants are actually in the pot: If you just bought broccoli, for instance, you will likely see three or four stems coming up from the soil. Congratulations- you just bought four broccoli plants, not one! The problem is, to grow properly, broccoli plants need to be spaced at least 12 inches apart. So you will either need to remove them from the pot and gently separate them, or you will want to cut off all but one plant. Because greenhouse space is valuable, nurseries have to overseed these containers, therefore it’s likely that most of the pots you buy will have more than one plant in it, so take a close look before you plant and make sure to space crops appropriately!!
Plant out quickly when possible: Do not plan to keep purchased plants in their pots for too long. It’s best to shop for plants a day or two before you plan to plant them. When small pots get set aside, it’s very easy to forget about them and let them dry out. If you do have to keep them in the pot for awhile after purchasing, feed them with an organic liquid fertilizer, make sure the receive adequate sunlight and don’t let them dry out.
Common annual crops we highly recommend transplanting INclude:
Fennel (annual bulb-types)