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What to Start Seeding and Planting in March

March is finally your time, gardeners—but you still want to be selective about what you seed this early.
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Gardener putting seed in soil
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If you're a gardening enthusiast, you've been waiting anxiously throughout February to start putting seeds in soil. March is finally your time, but you still want to be selective about what you seed this early. In fact, I’d say the number one problem gardeners have when they first start seeding is starting everything at once, and starting too early. It’s a long game between now and when you can put plants in the ground, and some plants need more time and space than others. On top of that, your planting date will be determined by your growing zone and last frost date—all things you can easily google.

Once you start seeding for yourself, you can also really lean into succession planting, which means planting a few of any given plant every week, instead of a whole package. As a result, you'll have, say, radishes ready to eat for a number of weeks, not a flush of them all at once. You can do this with lettuce and beans and flowers and all kinds of "short" crops (so called because they can be grown in less than 90 days). I’ll be offering a guide to what I’m seeding each month inside and outside, and while you don’t have to grow everything (I have never found space for peanuts) this will help remind you of the month’s possibilities. 

Asparagus, potatoes and onions

While it might not feel like these items are related, they are in the simplest way: You won’t be putting seeds in the ground. Onions are grown and cut back to the point you buy a bundle of 25 or so five inch long starts, ready to go into the ground. (These are keeping onions, not scallions.) Potatoes will look like, well, potatoes, but you cut them up so each piece has eyes, and then allow them to heal over and plant them. Asparagus come as crowns, which look like very, very sad desiccated roots. You plant them in a trench, not unlike roses, and they will make a perennial bed, coming back spring after spring. They’ve quite inexpensive, and while you could grow asparagus from seed, since you don’t get harvestable stalks for the first three years, it’s better to get a jumpstart by buying crowns.

Every kind of pea

Sweet peas (which are inedible and toxic but gorgeous and sweet-smelling) and their edible brethren can all be directly seeded outside right now. That’s shelling peas, snap peas, sugar peas. You can, if you want, give them a head start by growing starts inside, and they’ll generally be ready to plant out in two weeks. Plant a second bunch of peas two weeks after the first so you have a spring succession. These are perfect for climbing and giving your garden early color. 

Fast-rotation crops

There are certain crops I have going constantly all season, like lettuces, radishes, scallions, and carrots. I make sure that as soon as the ground is workable, I am putting out a short row of radishes and scallions, and then I seed a few lettuces each week at this point, and all of this can take place outside. Carrots aren’t fast, but you can get a number of successions in during the summer, and they’ll germinate easier while you have a lot of rain. Get a row of them in every few weeks starting now. 

Strawberries

Heed my cry: You never, ever need to buy strawberry plants. They multiple like tribbles, and you likely have enough from last year to relocate to anyplace you need them this year. You need to thin them yearly anyway so that each has at least six to eight inches around it. Even if you somehow do not have the supply, someone in your neighborhood does. Remember you want both June-bearing, which produces the sweetest berries but only for a short time, and ever-bearing, which produces bigger berries for the whole summer.

Short spring crops

There’s enough time between now and summer season to get another crop rotation in. Inside, I’m seeding cabbage, cauliflower, broccoli, kale, spinach, kohlrabi and chard to go outside as soon as they’re ready, since they’re all pretty cold hardy. Spinach, in particular, loves the cold. Outside, I’m seeding beets directly in the ground. 

Long summer crops

Two crops that don’t get enough attention this time of year but must be planted now, in order to have enough time to mature by winter, are parsnips and Brussels sprouts. Both take forever (well, 150 days), so get parsnip seeds in the soil and buy Brussels sprout starts at the nursery or get them seeding inside now and then out as soon as possible. 

Summer crops

Some summer specialties require a longer nurturing stage, like tomatoes, peppers and eggplants. But you absolutely cannot put them outside without protection like Agribon or a greenhouse until temperatures are 50 degrees at night, and that can be a long time from now. You’ll have to house, feed, and water these babies, much like annoying teenagers, until then. Every moment they’re in your care, they are susceptible to pests, virus, fungus and interference from family pets. You may see professionals getting their seeds in now—I’ll start mine around March 10th—but I have a greenhouse to move them to. Many people wait until April, and you shouldn’t feel anxious about doing so. Peppers first, then tomatoes, and finally eggplants. They’ll go into 50 cell trays to start, two seeds a cell. Within the first few weeks, I’ll have ruthlessly cut out one seedling from each cell (do not try to separate them to save them both, just learn to let go) and will be up-potting them into four-inch pots by the time they’re six weeks old. I don’t seed other summer crops like pumpkins, corn or beans until much later. 

Flowers

What I do try to get an early start on is flowers. I want as many as possible, and as big and healthy as possible before I put them in the ground. I start with the earliest flowers now—snapdragons, poppies, Bells of Ireland, larkspur, dianthus, bachelor buttons, Love-in-a-Mist, and celosia. These are the most stubborn to grow and are spring hardy, so the early start is warranted. You’ll be able to move them out relatively early in the season to make room for zinnias and sunflowers, which will be seeded later in the season. 

This time of year, as a gardener, it always feels like you’re behind. I assure you, you’re not. It’s still very early, but take this month, and get your ducks (and seeds) in order. Every year I have at least one germination failure and have to start over, so you want time for that to happen.