What to Plant in March: Seeds, Bulbs, and More

March is one of the most active planting months of the year, sitting right at the boundary between winter dormancy and spring growth. Depending on where you live, it can be the month you direct-sow hardy vegetables outdoors, get warm-season seeds started inside under lights, plant bare-root fruit trees, drop summer-blooming bulbs into the ground, or scatter wildflower seed. The key is matching what you plant to the conditions March actually gives you, which vary enormously by region and by week.

Cool-Season Vegetables You Can Direct-Sow

The vegetables that thrive when planted in March are the ones that prefer cooler temperatures and can handle a light frost. These include peas, spinach, lettuce, radishes, kale, arugula, carrots, beets, turnips, and members of the onion family like scallions and shallot sets. Most of these seeds germinate in soil temperatures as low as 4–10 °C (roughly 40–50 °F), which is well within March’s range for much of the temperate world. They actually perform worse in heat, so planting them early gives them the longest possible growing window before summer arrives.

Spinach is a standout example. It not only tolerates cold but actively becomes more cold-hardy when exposed to it. Research has shown that spinach seedlings can ramp up their freezing tolerance within a single day of cold exposure, reaching peak hardiness within about a week, thanks to the production of specific cold-acclimation proteins.¹ That means a March-sown spinach crop that encounters a late frost is far more likely to survive than you might expect. If temperatures climb back to warm levels, though, spinach loses that hardiness within days, so a sustained warm spell followed by a sudden frost can still do damage.

Peas are another classic March crop. They prefer soil around 10 °C and climb vigorously in cool, damp weather. The same goes for broad beans (fava beans), which in milder climates can even be fall-planted but are traditionally a March sowing in cooler zones. Root vegetables like carrots and parsnips germinate slowly in cold soil, so a March sowing means you might wait three weeks or more for sprouts to appear. Patience helps here: the seeds are viable, just slow.

Starting Warm-Season Seeds Indoors

March is the prime month for starting seeds indoors if you want transplant-ready seedlings of tomatoes, peppers, eggplant, squash, cucumbers, and herbs like basil. These plants need warm soil to germinate (typically above 18–21 °C) and cannot tolerate frost, so they stay inside until the danger of frost has passed, usually six to eight weeks after you start them. If your last expected frost date is in mid-May, that puts your indoor start date right around early to mid-March.

A few practical considerations make indoor starting more reliable. Seed-starting mix drains better than garden soil and is less likely to harbor fungal pathogens. A heat mat underneath the trays keeps the soil warm enough for fast, even germination, especially for peppers, which are notoriously slow starters in cool conditions. And once seedlings emerge, they need strong light. A south-facing windowsill sometimes works, but supplemental grow lights prevent the leggy, stretched-out growth that comes from low light.

One easy mistake is starting too early. Seedlings that outgrow their containers before outdoor conditions are ready become root-bound and stressed. Timing backward from your last frost date keeps everything on schedule. If you are unsure of that date, your regional agricultural extension service publishes frost-date maps based on decades of weather data.

Bulbs and Tubers for March Planting

March is not the month for spring-blooming bulbs like tulips and daffodils, which go in the ground in autumn and need a long cold period to bloom. Instead, March is when you plant summer-blooming bulbs and tubers: dahlias, gladiolus, lilies, begonias, canna lilies, and crocosmia. These store well over winter in a cool, dry place and are ready to go into the ground as soon as the soil begins to warm.

Gladiolus corms can go in as early as mid-March in mild climates, since they tolerate some cool soil. Planting them in successive batches two weeks apart gives you a staggered bloom period through summer rather than one big flush. Dahlias and cannas are more frost-sensitive and should wait until late March or even April in colder regions, or be started in pots indoors a few weeks before transplanting.

Lily bulbs are a slightly different case. Oriental and Asiatic lilies are often sold in spring and can be planted as soon as the ground is workable. They root quickly in cool soil and send up shoots when temperatures rise. If you find lily bulbs that have already started sprouting in the bag, get them in the ground immediately. Sprouted bulbs deteriorate fast in storage.

Seed potatoes also go in during March in many zones. Potatoes are technically tubers, not bulbs, but the timing overlaps. They want soil above about 7 °C and benefit from being “chitted” (set in a light, cool spot to sprout short green shoots) for a few weeks before planting. Early varieties planted in March can be harvested by June.

Bare-Root Trees, Shrubs, and Perennials

Late winter through early spring is the traditional window for planting bare-root stock, meaning trees, shrubs, and perennials shipped without soil around their roots. Fruit trees (apple, pear, plum, cherry), roses, berry bushes (raspberries, blackberries, currants), and ornamental trees are commonly sold bare-root and are usually cheaper than container-grown equivalents. The idea is to get them in the ground while they are still dormant, before buds break and new growth begins.

Research on bare-root planting confirms that the window matters. Stock that is lifted and planted while dormant establishes more reliably than stock handled after active growth has started, and for some species, the timing and condition of lifting are critically important to field performance.² March is ideal in most temperate climates because the soil has thawed enough to dig but the plants have not yet leafed out. Once you have bare-root stock in hand, plant it quickly. The exposed roots dry out fast, and even a day or two of neglect can set a tree back significantly.

Soak the roots in a bucket of water for a few hours before planting, dig the hole wide enough that roots can spread without being bent or circled, and plant at the same depth the tree or shrub was originally grown (usually visible as a soil line on the trunk). Water deeply after planting and mulch around the base, keeping mulch a few inches away from the trunk itself.

Wildflowers and Pollinator Habitat

March is an excellent time to sow wildflower seed, particularly in areas where you want to establish pollinator habitat. Many native wildflower species either germinate readily in cool soil or benefit from the natural cold exposure that a late-winter sowing provides. Scattering seed over prepared ground in March lets rain and fluctuating temperatures do some of the work of breaking dormancy.

Some wildflower species, including popular ones like Echinacea, actually require a period of cold, moist conditions to germinate well. Echinacea angustifolia seed, for example, needs at least two weeks of cold stratification to reach its maximum germination rate of around 65–80%.³ In laboratory studies of other species, cold stratification dramatically improved both germination rates and the speed of sprouting, with cold-treated seeds germinating in as little as one week compared to many weeks for untreated seeds.⁴ A March sowing onto cold, moist soil mimics this process naturally, which is why many wildflower growers swear by late-winter and early-spring sowing even though it seems counterintuitively early.

How densely you sow matters more than you might think. A study of pollinator plantings found that doubling seed density led to roughly a 24% increase in wild bee visits, because higher seeding rates produced greater ground cover of flowering species and richer species diversity.⁵ The same study found that thorough ground preparation before sowing had the greatest impact on long-term establishment. In practical terms, that means clearing existing vegetation, lightly raking the soil, broadcasting seed, and pressing it into contact with the soil surface rather than burying it deeply. Most wildflower seeds are tiny and need light to germinate.

Protecting Early Plantings from Late Frost

March weather is unreliable almost everywhere. A week of mild sunshine can be followed by a hard frost, and that volatility is the main risk of early planting. Row covers, cloches, and low tunnels are the standard defenses, and they work by trapping heat in the soil and buffering air temperature around the plants.

Row covers made from lightweight fabric raise both soil and air temperature around crops. Research on floating row covers found that soil warming was maintained from late spring well into early winter, even when the covers stopped warming the air effectively during the coldest months.⁶ That soil-warming effect is especially valuable in March, because many seeds and transplants are more sensitive to cold soil than to cold air. The covers work by reducing heat loss from the soil surface, not just by trapping warm air underneath.

Low tunnels, which are essentially miniature hoop houses made from bent wire or PVC hoops draped with plastic or fabric, are even more effective. Studies have measured average air temperature increases of about 3 °C and soil surface temperature increases of about 1.2 °C inside low tunnels compared to uncovered ground, with peak daytime differences as large as 5–6 °C.⁷ That difference can be enough to keep a young tomato transplant alive through a late frost that would otherwise kill it. Low tunnels are cheap to build, easy to ventilate on warm days (just push the covering aside), and reusable for years.

For individual plants rather than rows, a cloche (a glass or plastic dome placed over a single plant) works on the same principle. Even an upturned plastic bottle with the bottom cut off can protect a small seedling overnight. The key is remembering to vent or remove the cover during warm days so plants do not overheat or develop fungal problems from trapped humidity.

The Risk of Planting into Cold, Wet Soil

There is a real downside to jumping the gun in March. Cold, saturated soil creates ideal conditions for soil-borne pathogens, especially species of Pythium, a group of fungus-like organisms that cause damping-off, where seedlings rot at the base and collapse. Research on soybean found that germinating seeds and young seedlings exposed to cold stress at the time of infection suffered significantly more root rot and damping-off than those that had already emerged and established.⁸ The problem is compounded when planting dates shift earlier, because seeds sit in cold soil longer before germinating, giving pathogens more time to attack.

This risk applies across many crops, not just soybeans. Peas, beans, corn, and cucurbits are all susceptible to damping-off in cold soil. A few practical steps reduce the danger:

• Wait for drainage: If the soil is waterlogged, give it a few more days. Squeeze a handful of soil; if water drips out, it is too wet.
• Use treated seed: Some seed is sold pre-treated with fungicide or biological inoculants that suppress Pythium. This is especially common for peas and beans.
• Raised beds: They drain faster and warm sooner than flat ground, reducing the window of vulnerability.
• Shallow sowing: Seeds planted closer to the surface warm faster and emerge sooner, spending less time in the danger zone.

How March Planting Differs by Region

March planting advice always comes with the caveat that your specific climate determines what is possible. A gardener in the southern United States or Mediterranean Europe can direct-sow warm-season crops in March, while someone in northern New England or Scandinavia may still be looking at frozen ground. The simplest way to calibrate is by soil temperature rather than calendar date.

Analysis of global crop planting patterns shows that spring wheat is typically planted when daily average air temperatures are in the range of 8–14 °C, while maize (corn) planting in the northern mid-latitudes usually waits until temperatures reach about 12–17 °C, with soil moisture often being the limiting factor rather than temperature alone.⁹ Those benchmarks are useful even for home gardeners: if the soil is warm enough for wheat, it is warm enough for most cool-season vegetables. If it is warm enough for corn, warm-season crops can go in directly.

In USDA zones 7–10, March is already solidly into spring planting season. Tomato and pepper transplants can go outdoors in zone 9 and 10 gardens by mid-March. In zones 5–6, March is for cool-season direct sowing and indoor seed starting, with warm-season transplanting pushed to May. In zones 3–4, March may still involve snow cover, and the main productive activity is starting seeds indoors under lights. Knowing your zone gives you a rough calendar, but a soil thermometer gives you the final answer.

Herbs, Perennials, and Ornamental Grasses

Several perennial herbs handle March planting well. Chives, oregano, thyme, and mint are cold-tolerant and can be divided or transplanted in early spring while still semi-dormant. Parsley and cilantro can be direct-sown; both are cool-season crops that bolt quickly once summer heat arrives, so an early start gives you the longest harvest. Dill is another cool-weather performer, though it dislikes transplanting and should be sown directly where you want it to grow.

For ornamental gardens, March is the time to divide and replant summer- and fall-blooming perennials. Hostas, daylilies, sedums, asters, and ornamental grasses can all be divided as they start showing new growth at the crown. Dividing in early spring lets them re-establish roots in cool, moist soil before the demands of summer. Fall-blooming perennials in particular are best divided in spring rather than fall, since cutting them apart in autumn leaves little recovery time before winter.

Ornamental grasses are worth special mention because they are one of the few plant groups that should not be cut back until late winter or early spring. The old foliage insulates the crown over winter. Cut them back to a few inches in March, just before new growth begins, and this is also a good time to divide clumps that have developed a dead center.

Container Planting and Small-Space Strategies

If you garden in containers on a balcony or patio, March gives you a head start because containers warm up faster than in-ground beds. Soil in a dark-colored pot sitting in the sun can be several degrees warmer than the surrounding garden soil, making it possible to sow cool-season crops a week or two earlier than you would in the ground. The trade-off is that containers also cool down faster at night and freeze more readily in a hard frost, so be ready to move pots against a warm wall or cover them on cold nights.

Lettuce, radishes, spinach, and herbs like cilantro and parsley are natural fits for March container planting. You can also start potatoes in large containers or grow bags, layering soil over the seed potatoes as the shoots grow (a technique sometimes called “earthing up”). Strawberry plants sold as bare-root crowns can go into containers in March and will produce fruit by early summer.

Window boxes planted with cool-season flowers like pansies, violas, and snapdragons add color right away. These plants thrive in the cool temperatures of early spring and keep blooming until summer heat replaces them. In mild climates, sweet peas can be sown directly into tall containers with a trellis; they climb fast and produce fragrant blooms for weeks.

Lawn and Ground-Cover Renovation

March is a practical time to overseed a thin lawn or patch bare spots. Cool-season grass types like fescue, ryegrass, and bluegrass germinate best in cool, moist conditions, and a March sowing gives the new grass time to establish before summer stress. Scratch the bare soil lightly with a rake, scatter seed, press it into contact with the soil, and keep it moist. A thin layer of compost over the seed helps retain moisture and provides a small nutrient boost.

Ground-cover plants like creeping thyme, ajuga, and clover can also be planted or divided in March. These are increasingly popular as partial lawn replacements, especially in areas where reducing mowing and watering is a goal. Clover in particular fixes nitrogen from the air into the soil, reducing the need for fertilizer, and its flowers support pollinators through spring and summer.