To think about what to plant in your garden in March, you need to think in categories. Of course, you also need to have an idea of the average date of the last frost, which is approximately mid May in southwest Idaho. When I say plants, I am including all the ways that you might get a plant, from seeds, purchased seedlings, bulbs, or roots. I am going to emphasize edible plants this time around. The categories that I have come up with are:
- plants that will not be harmed at all by a freeze
- plants that can germinate in cool soil
- plants that prefer to germinate and grow in damp soil
- plants that can be divided or transplanted
- plants that can handle a light frost, depending on the stage of growth
- plants that have been appropriately hardened off
- plants that should have been started last fall, but will be passable to plant in late winter
- plants that are sprouting volunteers already
- plants that are easy or inexpensive to replace, if necessary
- plants that can be started in the greenhouse
- plants that you want to harvest at the same time as other plants
- plants that have more trouble with insects or disease depending on the weather
Some of these categories overlap, but they are all useful to think about for a given plant. For instance, the plants in this first list can be planted as soon as the ground can be prepared to accept the seed. In fact, in this arid region of Idaho, most of the plants in the list directly below will not grow or produce well later, because of the dry scorching heat that no amount of watering can compensate for. Fortunately, these are the same plants that tend to thrive in the cool rains of spring. There is just enough time, usually, to enjoy them before the heat hits.
Cilantro might also be something you want to time a harvest of when your tomatoes are ripening, but since it is a fast, vigorous grower, you can probably have multiple small crops. I have quite a lot of little cilantro volunteers right now. Dill will volunteer almost as early, but those plants are usually well past the stage desirable for making dill pickles when cucumbers are ripe, so a later planting may be desired to coincide with the warm weather crop of cucumbers. (click on any photo to enlarge)
Cole crops are not usually planted quite as early as the above crops, more toward mid to late March, but have more trouble with aphids if they are held over into the warmer parts of the summer.
- early cabbages
I often have things like leeks and onions that have overwintered. Some of them are perennials, like my bunching onions, and are showing lots of crisp, green blades in early March. They can be divided or thinned in March if they are showing signs of vigorous growth. Sometimes I also have volunteers from fall seed heads that can be transplanted to a more convenient location on a sunny, late winter day. To continue with the list format:
The garlic is something that grows to the best size when planted in the fall, but I have heard of many friends not getting it planted until late winter and saying that smaller garlic is better than none at all!
Some plants tend to be more of a monetary investment from the start, so you want to be more careful of finding the most agreeable time to have them outdoors. If you are willing to keep a daily eye on the temperatures, both day and night, you can risk more. They might need to be covered every night and some days, but, equally important, they might need to be uncovered some sunny days so that they don’t cook. This might include larger or more exotic seedlings that are likely more expensive, roots or tubers that are sold by the pound, and seeds that are expensive. The only plants that I think of in this category right now are:
For any of these cool weather crops that will grow, without stress, in the late winter to early spring weather, please remember that if they were started in the greenhouse, they still need to be hardened off gradually to be able to handle life outdoors. This includes becoming accustomed to all the elements of sun, wind, andcooler temperatures.
If this doesn’t feel like enough to plant, remember that you can start quite a number of seeds in your greenhouse or using grow lights at this time. There will not be an advantage to starting all your warm weather crops this way, and in some ways you may create problems for yourself. (If you are interested in some guidelines for which seeds to start indoors, read here) Still, you should have plenty to do since the weeds will be sprouting, too (read some about my weeding strategies here), and there might still be some fall clean-up to do.
This overall planting schedule, that I wrote 2 years ago, is still a good monthly list, although I have been known to push the limits and experiment. Sometimes, it is just a matter of how I feel, and, as mentioned above, usually with something that is not too much of a monetary investment. But sometimes I change it up because the weather seems to suggest it. I don’t mean the normal fluctuations and teasings of the capricious spring weather, but a real run of a particular type of weather that I need to adjust to, such as a long hot spell that is stressing out my seedlings in pots or a long rainy spell so that I hold off planting melons and squashes.
So where am I with things this March, so far? I have peas, some lettuce, and some of my broccoli planted. I am going to get the spinach done soon! I’m working on site prep for transplanting my only blackberry plant. And I still need to get some of the old bean vines off of a trellis. I’m weeding and thinking about where I want to mulch more this year. But during it all, I’m keeping in mind my attempts to have realistic goals, so that I have a higher chance of enjoying the whole gardening season.