15 Vegetables to Start Seeding in April

Spring has finally arrived and you can’t wait to dig into your garden. But before you start planting warm-weather crops, you want to be sure that your soil has sufficiently warmed and nighttime temperatures are thoroughly settled.

Northern gardeners in hardiness zones 5 and colder may still have snow on the ground, but hardiness zones 6-9 are gearing up for the glory days of summer.

After 8 years of vegetable farming in growing zones across the United States, I’ve caught on to a few sneaky tricks that farmers use to get the earliest yields possible. Here are my favorite vegetables to seed in April, based on your hardiness zone.

Tomatoes

• Soil Temperature: 75-90°F
• Seeding Rate: Sow ¼” deep in 6-packs or cell trays and pot up to 4” containers at the first true leaf. Transplant in the garden after 4-6 weeks when night temperatures are consistently above 50°F. Plant about 12-24” apart (determinants) or 24-36” apart (indeterminate) in rows 2-4’ apart.
• Start Indoors in These Zones: Zones 4-6
• Start Outdoors in These Zones: Transplant out in zones 7-10. Direct seeding is not recommended.

By spring, gardeners are craving to get tomatoes growing in time for summer! Thankfully, April weather usually means it’s time to seed tomatoes indoors in zones 4-6.

Gardeners in hardiness zones 7-10 should already be transplanting their tomatoes out in the garden! If you forgot to seed tomatoes, no worries! You can always start now or purchase established seedlings from your local nursery.

The most important thing to remember when seeding tomatoes is: provide plenty of sunlight and do not seed too soon. Tomato seedlings can become very leggy if they don’t have enough light. They can also get rootbound if they are left in their pots for too long. You should seed tomatoes a maximum of 6 weeks before transplanting.

If you are having an exceptionally cold spring, wait an extra week or so. Heating mats make a huge difference for germination and early establishment of this tropical nightshade. Grow tomato seedlings at a constant 60-70°F ambient temperature.

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Peppers

• Soil Temperature: 80-90°F
• Seeding Rate: Sow ¼” deep in cell trays or 6-packs; transplant 12-18” apart in rows 24-36” apart
• Start Indoors in These Zones: Zones 4-8
• Start Outdoors in These Zones: Zones 9-12

Whether you prefer hot peppers, bell peppers, shishitos, or Italian peppers, these nightshades are slow-growing and best established in the spring.

For zones 4-8, sowing peppers indoors in April gives them a head start to begin producing by late June or early July. Warmer zones should’ve started peppers in late February or March, but you can still seed in the garden or plant store bought seedlings outside.

Start peppers indoors about 8 weeks before transplanting out. Like tomatoes, peppers prefer a toasty 60-70°F ambient temperature during establishment. The seeds germinate very slowly in cold soil, so be sure that your container soil hovers around 80-90°F. A heating mat makes a huge difference!

Carrots

• Soil Temperature: 60-85°F
• Seeding Rate: ¾-1” apart, ¼-½” deep, in rows 16-24” apart
• Start Indoors in These Zones: Carrots can only be direct-seeded.
• Start Outdoors in These Zones: Zone 6-12

In most temperate climates, April is prime time for planting and growing carrots. Carrots may germinate slowly and erratically in the chilly weather of March, but by April the days are usually warm enough to promote germination. Still, the nights are cool enough to keep the roots crisp and sweet.

In zones 4 and colder, you may still need to use a low tunnel, row cover, or wait a few more weeks to seed your carrots. Zones 5 and warmer can comfortably sow without protection.

If you get carrot seeds in the ground by early April, you’ll likely be harvesting sweet orange (or purple or white) carrots by June. Don’t forget to thin your carrots as soon as they come up to prevent overcrowding!

Sweet Potatoes

• Soil Temperature: 60-80°F
• Planting Rate: 12-18” apart in rows 2-3 feet apart
• Start Indoors in These Zones: Not recommended
• Start Outdoors in These Zones: Zone 7-12

About 2-3 weeks after your last spring frost date has passed, it’s time to plant the highly coveted sweet potato! These tubers are very frost-sensitive and should only be planted when you are certain that the weather has fully settled.

Sweet potatoes are started from “slips” rather than seeds. Slips are technically mini sweet potato runners that are planted similarly to “seed” potatoes. Both forms of vegetative propagation yield plants that are genetically identical to the parent. They also give you a much quicker start to the season compared to true seeds.

For zones 5 and colder, you may want to wait until May or June to plant sweet potatoes. In unpredictable climates, it is highly recommended to use row cover or low plastic tunnels to protect the tender slips from unexpected dips in nighttime temperatures.

Some gardeners cover sweet potato beds with black plastic for a week before planting to ensure the soil is extra warm and moist.

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Read Also: What is Water Footprint Assessment?

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Strawberries

• Soil Temperature: 60-80°F
• Planting Rate: Space crowns 12-18” apart in rows 2-4” apart. If you plan to prune regularly, you can plant closer to 5-9” apart with staggered rows about 10-20” apart.
• Start Indoors in These Zones: Zones 2-4
• Start Outdoors in These Zones: Zones 5-9. Subtropical zones 10-12 should plant strawberries in the fall and harvest in the winter and spring.

Strawberry crowns are finally ready to go in the ground when the chances of frost have passed. You can technically plant strawberries a little bit earlier, as long as nighttime temperatures are above 25-30°F. In a normal year, zone 5-9 gardeners can get strawberries in the ground in mid to late April.

Ideally, you’ve prepared your perennial strawberry beds in the previous fall to ensure that weeds are under control. If not, there is still time to weed, water, and throw a tarp over the bed for a week before planting.

If you want to harvest berries this year, choose a day-neutral variety like ‘Albion’ or ‘Seascape’. These varieties will begin fruiting as early as July and continue until the frost. Any June-bearing or everbearing crowns planted in April may not yield until summer of the following year.

Peas

• Soil Temperature: 70-90°F
• Seeding Rate: 1.5-2” apart, ½-1” deep, in rows 18-36” apart
• Start Indoors in These Zones: Zones 5 and colder
• Start Outdoors in These Zones: Zones 5-9

Sugar snap peas and snow peas love the cool weather of spring. In fact, southern zones need to get peas in the ground before the weather gets too hot or else the peas may have trouble yielding.

You can direct seed these delicious legumes as soon as the soil can be worked. Before seeding, install a simple trellis with T-posts and a cattle panel.

If you still have snow on the ground, start your peas indoors in cell trays. Sow 1-2 seeds per cell and transplant as soon as you can get into the garden. Peas are not recommended for spring gardeners in subtropical zones.

Basil

• Soil Temperature: 75-85°F
• Seeding Rate: Direct seed ¼” deep, 2-3 seeds per inch, in rows 18” apart. If transplanting, plant ¼” deep with 1-2 seeds per cell. When seedlings have 3-4 sets of leaves, transplant at 4-8” apart in rows 18” apart
• Start Indoors in These Zones: Zones 3-8
• Start Outdoors in These Zones: Zones 9-12

Basil is a tender annual that thrives in the heat. In zones 8 and warmer, you should be able to confidently plant basil outdoors. However, northern gardeners will likely want to give this warm-weather crop a head start inside as you wait for the spring weather to settle.

Indoor seedlings usually take 4-6 weeks to mature and will eagerly transplant once your garden soil has reached a consistent 70°F. Zones 4-5 gardeners may want to wait until the end of April to start their basil.

Basil typically takes 5-10 days to germinate. For the best germination, keep basil at an ambient temperature of around 70°F. A seed tray heating mat will work wonders for germination and initial plant vigor. These plants love cozy warm soil and lots of sunlight.

If direct seeding basil, I highly recommend using row cover to add extra warmth and protect the young plants from pests. On commercial organic farms, we used black landscape fabric (with holes burned in it) or plastic mulch to ensure extra heat in basil beds while keeping weeds at bay. This dramatically improved early summer yields for those who are craving pesto!

Broccoli or Broccolini

• Soil Temperature: 68-85°F
• Seeding Rate: Sow 2 seeds per cell about ¼” deep and thin to the strongest plant. After 3-4 weeks, transplant outdoors 10-18” apart in rows 18-36” apart (for full size heads) or 6-12” apart (for mini broccoli).
• Start Indoors in These Zones: Zones 4-8
• Start Outdoors in These Zones: Direct seeding broccoli is rare. Transplants are recommended.

Broccoli is yet another cool weather crop that does best as a transplant. This delicious brassica prefers ambient temperatures around 55-75°F. Southern gardeners should already have their broccoli in the ground, but northern growers are entering the perfect window of opportunity for April brassicas.

If you start broccoli indoors in early April, you can plant it outside by May and harvest by late May to early June before the weather gets too hot.

For impatient gardeners, try out a broccolini, mini broccoli, or sprouting broccoli variety! My personal favorites are ‘Happy Rich, ‘De Cicco,’ and ‘Melody’. These cultivars can mature in half the time of a regular broccoli plant. The tender stems and florets offer continuous harvests of broccoli shoots rather than big rounded heads.

Because you can harvest broccolini for many months of the season, they are sort of like the gift that keeps on giving. Unlike broccoli, you don’t have to pull out the plant one the central head yields. Instead, they just keep putting out new shoots!

Asparagus

• Soil Temperature: 50-70°F
• Planting Rate: 12-18” apart in trenches 18” apart
• Start Indoors in These Zones: Starting from seed and transplanting is not recommended. Order bare root crowns.
• Start Outdoors in These Zones: Zones 5-10; Zones 1-4 should wait until May

April is the time to establish a new perennial asparagus patch! While asparagus can be planted in the autumn, most garden stores and seed companies have the best selections of bare root crowns in the spring. You can plant asparagus as soon as the soil can be worked and the chances of first are gone.

Bare root asparagus crowns are similar to strawberry crowns because they are dormant year-old plants rather than true seeds. This means that they will establish more quickly and reliably than asparagus seeds.

Asparagus needs a permanent perennial bed with full sunshine and plenty of drainage. For the best results, prepare the bed, then water the soil and lay a black tarp over it for 2-3 weeks before planting.

This will help kill off any aggressive weeds. For an extra buffer against perennial weeds, lift the tarp every couple of weeks, water it, and get more weeds to sprout before smothering them again.

Plant asparagus crowns as soon as possible after you get them! Dig a trench 12-18” wide and about 6 inches deep. Place the crowns 12-18” apart in the trench with the buds facing up and roots facing down. Cover with 2” of soil and continue to mound the soil as they grow. You can also mulch heavily with straw or dried leaf litter.

You won’t be able to harvest your asparagus for another 2-3 years, but once the patch is established, you can enjoy asparagus spears for the next 25 years or more! Trust me, it’s worth the wait!

Rhubarb

• Soil Temperature: 40-60°F
• Planting Rate: 4-6 feet apart in every direction
• Start Indoors in These Zones: Transplanting is not recommended. Start with bare root crowns.
• Start Outdoors in These Zones: Zones 3-6, as soon as soil can be worked

Rhubarb is another long-lived perennial that prefers to get established during the cool days of early spring as soon as the ground thaws. These tangy plants will produce for the next 8-10 years, so it’s important to establish a nice permanent garden bed for them to thrive.

Because they are so prolific, most gardeners don’t need a bunch of rhubarb plants. A handful of plants is plenty for a normal family.

Because of its space requirements, small space gardeners may want to avoid rhubarb altogether. Gardeners in zones 8 and warmer cannot usually grow rhubarb because the temperatures don’t get low enough to prompt dormancy.

Corn

• Soil Temperature: 65-80°F
• Seeding Rate: Sow ¾-1” deep, 6-7” apart, in rows 30-36” apart
• Start Indoors in These Zones: Zones 3-6
• Start Outdoors in These Zones: Zones 7-12.Zones 6 and colder should wait until May to seed corn outside.

If you haven’t had a frost in two weeks, congrats! It’s time to plant corn! This grass-family veggie loves the warmth and sunshine. Corn cannot handle frost or any cold weather under 50°F. If you plant in mid to late April, you can typically harvest the ears by early July, about 2-3 weeks after the ear silks first show. Warmer weather means quicker harvests!

While most gardeners think of corn as a direct sown crop, many professional vegetable farmers in northern zones have started to transplant the crop.

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Read Also: Water footprints – need to calculate to avoid a water crisis.

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This works exceptionally well in states like New Hampshire, Montana or North Dakota. You can start corn indoors with a similar method to peas. Sow 1-2 seeds per cell in 72 or 150 cell trays. Use a seedling heat mat for best results. After 10-14 days, transplant outdoors.

For a continuous supply of sweet cobs, stagger your corn plantings every 10-12 days and use multiple different varieties. Just be sure that your super-sweet or non-super sweet varieties don’t cross-pollinate.

The easiest way to do this is by separating the plantings in different parts of the garden (about 25 feet apart) and planting them at least 2 weeks apart so they mature at different rates.

Green Beans

• Soil Temperature: 60-90°F
• Seeding Rate: Sow 1” deep, about 3” apart, in rows 2-4’ apart
• Start Indoors in These Zones: Zone 4-5
• Start Outdoors in These Zones: Zone 6-10

When your soil thermometer probe reads 60°F, you can safely plant beans in the garden! For zones 6 and warmer, mid-April is usually a safe time to get these tender legumes into the garden.

Both pole beans and bush beans can be seeded at this time. If you choose pole beans, ensure that you create a trellis before planting.

Beans mostly prefer direct seeding, but northern growers can start green beans indoors about 2-3 weeks before transplanting in the garden. Be careful not to disturb the roots.Use a legume seed inoculant or diluted kelp solution for the quickest establishment.

Zucchini

• Soil Temperature: 60°F-65°F
• Seeding Rate: Space plants 18-24” apart in rows 3-5’ apart, wider spacing makes harvest easier but dwarf varieties can be planted closer together
• Start Indoors in These Zones: Zones 6-7, Zones 5 and colder should wait until May
• Start Outdoors in These Zones: Zones 8-9

Zucchini is a cucurbit-family that loves warm weather. These plants have very sensitive roots, which is why direct seeding is recommended. However, you need to be sure that your garden soil has sufficiently warmed to around 70°F. For zones 8-9, this may mean waiting until late April or several weeks after the last frost date.

In zones 6 and 7, you can get away with starting zucchini indoors under specific conditions. Summer squash matures very rapidly, so be sure you only start seeds in containers about 2 weeks before transplanting.

Starting too soon could cause rootbound plants or flowering in the pot, which may stunt the plants by the time they get in the garden. Be very careful when transplanting because the roots of zucchini are extremely vulnerable to disturbance.

Cucumbers

• Soil Temperature: 75-90°F
• Seeding Rate: Sow ½-¾” deep, 12” apart, in rows 4-6’ apart or closer if using a trellis
• Start Indoors in These Zones: Zones 6-7
• Start Outdoors in These Zones: Zones 8-10

Like zucchini, cucumbers are a tender crop that cannot handle any cold weather. Make sure that the soil and air temperatures are reliably warm before even taking your chances with cucumbers.

For zones 8 and warmer, April usually puts you in the clear. Zones 7 and colder should monitor temperatures carefully and wait until May if the spring weather is tricky. A low plastic tunnel, row cover, or a greenhouse can make a huge difference if you crave crisp early cucumbers!

Cukes also despise root disturbance, which makes transplanting precarious (but not impossible). Direct sowing beneath a row cover is certainly the best option.

If you want to transplant, be sure that you start cucumbers in 4” pots just 3-4 weeks before planting out. Use a heating germination tray and water-in with a diluted kelp solution to prevent transplant shock.

Beets

• Soil Temperature: 55-85°F
• Seeding Rate: Seed ½” deep, 3-4 seeds per inch, in rows 12-18” apart
• Start Indoors in These Zones: Zones 3-5
• Start Outdoors in These Zones: Zones 6-9

These cold-hardy roots are ready to go in the ground any time in the spring, as long as soil temperatures are above 45°F (optimally between 55° and 85°). For northern gardeners, this means that you can seed beets outside as soon as the soil can be worked.

For a continuous supply of beet greens or baby tender beets, stagger your seedings every 2 weeks. Beets are a chard cousin that also offer delicious greens for baby salad green mixes. You can even select orange, yellow, or candy-cane-striped (Chioggia) beets to add some color and flavor to spring roasts.