I remember being surprised when I learned that okra isn’t a vegetable. Because it’s a seed-bearing product of fertilization, okra is botanically defined as a fruit. The same is true of other popular “veggies” like peppers, cucumber, squash, corn, and eggplant. Unless you’re a botanist, the botanical differences between a fruit and a vegetable probably aren’t all that fascinating, but when it comes to gardening, there are a couple of differences worth noting.
In Baja Arizona, true veggies rule the winter garden, as they often require cooler temperatures to develop good flavor, or bolt too quickly in high temperatures. Rather than being the result of a pollinator’s hard work, real vegetables come from the vegetative parts of a plant such as roots, stems, leaves, or buds. Fruit, on the other hand, often needs heat to develop good flavor, and many types of fruit won’t develop at all in the absence of pollinators. It makes sense that fruit is more abundant in summertime.
Fruit is generally designed to be plucked from the plant (or to fall to the ground if it goes unplucked), so harvesting repeatedly from the same plant doesn’t usually cause it much distress. When we harvest a vegetable, however, we’re removing parts of the plant that it uses to produce, store, or transport nutrients or water. Some of the leafy veggies can be plucked repeatedly, but most of our root veggies can only be harvested once.
Luckily, we can begin sowing root veggies just after monsoons in August or in early fall. Starting this early takes advantage of warm days that can help speed up germination, and then cooling temperatures as roots begin to develop. If you didn’t start early, there’s still time to get a harvest or two out of crops like carrots, beets, and radishes before it gets too warm, especially if you choose bolt-resistant or heat-tolerant varieties. Plant another batch every two to three weeks through March or April to extend the harvesting window through winter and into early summer if you live at higher elevations or if the weather is kind. Planting successively allows you to harvest just what you and your family can use each time.
Direct seeding in the garden is the recommended method for starting root veggies, since they’re notoriously difficult to transplant. However, the seeds can be very tiny and difficult for some of us to handle or manage. Arranging seeds on seed tape can be a helpful tool in planting easy rows of tiny seeds with less seed waste and less need for thinning later on. Seed tape is something that you can “glue” seeds to and then plant in the ground in strips. Good seed tape decomposes as the seeds sprout and grow. You can sit down at the kitchen table and glue the seeds down on strips of cheap, 1-ply toilet paper with a weak flour/water paste at whatever spacing they need, then plant the strips of tape for straight rows that require less thinning than seedlings that were planted by the pinch.
Consider planting in a raised bed or in planters that can be protected if rabbits are a problem in your garden. Even the deep-rooted veggies like carrots can grow in containers that are at least 10 to 12 inches deep and wide. Some gardeners prefer growing root veggies in raised beds or planters because it’s easier to create the ideal loose and obstruction-free soil that they grow best in. Patches of caliche, rocks, or hard clay are common causes of misshapen carrots, parsnips, and other deeply-rooted veggies.
I think most gardeners would agree that the long wait for results is the most difficult part of growing root crops. A few radish varieties germinate in about a week and are ready to eat in as few as 24 days (in the case of Cherry Belle). Other root vegetables can take two or three weeks to germinate, and it can be more than 70 days until they’re ready for the table. Parsnips are particularly slow, some needing as long as 110 days before they’re ready to harvest. In general, the faster a root crop matures, the later into the season you can plant it.
Once they’ve germinated and are going strong with enough top growth, it’s time to thin your veggies to the proper distance to give each plant plenty of space. There’s no need to bother with thinning if you happen to be growing a root crop solely for its greens, but if you want those nice, large roots, they need room to grow. Overcrowding is another common cause of stunted or deformed root crops.
It’s usually recommended to thin with a pair of snips to diminish root damage to the plants you’d like to keep, but I love to pull at least a few of the small, sweet carrots. I always feel a bit crummy about removing a seedling that I planted, but snipped baby greens and tiny carrots in my salads make this chore a little less heartbreaking.
Fertilize carefully as your crops grow. Root veggies are generally light feeders, and too much nitrogen can motivate them to favor leafy growth over root development. This is fine if you’re growing them for their greens, but it can cause roots to be stunted and less flavorful. It’s a good idea to work these light feeders into a spot where there were heavier feeders like summer squash or melons the previous season. Radish is one of the heaviest feeders of the root crops, which might have something to do with how fast it grows.
Check on the size of the roots just under the surface as you get closer to the harvest date. Dig up a tester from time to time, and harvest when the flavor is just to your liking. Younger root veggies often taste milder and sweeter, while those left in the ground for too long can get woody and develop a bitter flavor.
Seed packets are pretty good about telling you what to do with their contents, but the information isn’t always printed for our region. Here’s a quick guide to growing some of the most popular root veggies here in Baja Arizona.✜
Amy Belk is a garden writer and photographer, a certified arborist, and a certified nursery professional who has been learning from her garden for 15 years. She and her husband homestead on a little piece of the desert in the heart of Tucson.