Start with what grows best in shallow soil and containers

Raised beds work best for plants with shallow root systems and those that need good drainage. Vegetables like lettuce, spinach, radishes, and bush beans produce well in 8 to 12 inches of soil. Herbs such as basil, parsley, and chives thrive in raised beds because they prefer soil that doesn't stay wet. Root vegetables like carrots and beets need deeper beds—at least 12 inches—but still perform better in raised beds than in compacted garden soil because the soil stays loose and crumbly.

The depth of your raised bed matters more than its width. A bed that is 4 feet by 8 feet but only 6 inches deep will limit you to shallow-rooted plants. A bed that is 3 feet by 3 feet but 18 inches deep gives you far more options. Before you plant, measure your bed's depth and match it to what you want to grow.

Key Takeaways

  • Lettuce, spinach, radishes, and herbs need only 8 to 12 inches of soil and are the easiest crops for shallow raised beds.
  • Root vegetables like carrots, beets, and parsnips require at least 12 inches of depth to develop properly without forking or stunting.
  • Tomatoes, peppers, and eggplants need 12 to 18 inches of soil and benefit from the warmth that raised beds provide earlier in spring.
  • Avoid planting trees, large shrubs, or perennials that spread underground in raised beds because they will outgrow the space or damage the structure.
  • Fill your bed with a mix of topsoil, compost, and peat moss or coconut coir rather than garden soil alone, which compacts over time.

Shallow-rooted vegetables that produce quickly

Lettuce and spinach are the workhorses of raised beds. Both grow in 6 to 8 inches of soil and are ready to harvest in 30 to 45 days from seed. Plant lettuce in spring and again in late summer for a fall crop—it bolts and turns bitter in summer heat. Spinach tolerates cold better and can be planted in early spring or late summer. Both can be harvested leaf by leaf as they grow, so one planting feeds you for weeks.

Radishes mature in 25 to 30 days and take up almost no space. Plant them between slower-growing crops like tomatoes or peppers, and they will be gone before those plants need the room. Arugula, mustard greens, and Asian greens like bok choy also thrive in raised beds and tolerate partial shade, which is useful if your bed sits near a fence or building.

Bush beans (also called snap beans or string beans) need 8 to 10 inches of soil and produce heavily in a small space. Plant them after the last frost date when soil is warm. They mature in 50 to 60 days and keep producing if you pick them regularly. Avoid pole beans in a raised bed unless you have a sturdy trellis, because they need more vertical space than most beds provide.

Root vegetables that need deeper beds

Carrots, beets, and turnips need at least 12 inches of soil to develop straight roots without forking or splitting. In shallower soil, they grow stunted or misshapen. Carrots take 60 to 80 days to mature, so plant them early in spring for a summer harvest or in midsummer for a fall harvest. Beets are faster—50 to 70 days—and the greens are edible, so you get two crops from one plant.

Parsnips and salsify are slower (100+ days) but worth growing if you have the space and patience. Both store well in the ground through fall and early winter, so you can harvest them as you need them. Radishes and turnips are faster alternatives if you want a root crop but don't want to wait as long.

Tomatoes, peppers, and eggplants for warm-season beds

These heat-loving plants need 12 to 18 inches of soil and benefit from the extra warmth that raised beds provide. Soil in a raised bed warms up 2 to 3 weeks earlier in spring than ground-level soil, so you can plant transplants (not seeds) earlier and harvest sooner. Determinate tomatoes (bush types) fit raised beds better than indeterminate (vining) types, which need tall stakes or cages and can shade the rest of your bed.

Peppers and eggplants are slower to mature than tomatoes—80 to 100 days—but they produce steadily through summer and into fall if you keep picking. Both prefer warm soil and air, so wait until nighttime temperatures stay above 60°F before planting. Space them 12 to 18 inches apart so air can circulate and prevent disease.

Tomatoes are heavy feeders and will deplete soil nutrients by mid-summer. Mix compost into the top few inches of soil every 4 to 6 weeks, or use a balanced fertilizer every 2 to 3 weeks once plants start flowering. Peppers and eggplants are less demanding but still benefit from a feeding every 4 to 6 weeks.

Herbs that prefer good drainage

Basil, parsley, chives, and oregano thrive in raised beds because the soil drains quickly and doesn't stay waterlogged. Basil is an annual and needs warm soil—plant it after the last frost date. It grows fast and produces leaves for 8 to 10 weeks before flowering. Pinch off the flower buds to keep it producing longer. Parsley is a biennial but is usually grown as an annual in raised beds. It tolerates partial shade and takes 70 to 90 days to reach full size.

Chives, oregano, and thyme are perennials and will come back year after year if you don't harvest them too heavily in their first season. Plant them in a corner of the bed where they won't be disturbed during spring digging. Mint spreads aggressively underground and should be grown in a pot sunk into the bed, not planted directly, or it will take over.

Flowers and companion plants for raised beds

Marigolds, nasturtiums, and zinnias grow well in raised beds and attract pollinators to your vegetables. Marigolds and nasturtiums are also edible—the petals add color to salads. Both are annuals and bloom until frost. Zinnias need full sun and warm soil but produce flowers for months once they start blooming.

Borage and calendula are traditional companion plants that some gardeners plant near vegetables to attract beneficial insects. Borage flowers are edible and taste like cucumber. Calendula (pot marigold) has antimicrobial properties and is sometimes used in herbal remedies, though it is grown mainly for its bright orange flowers.

Plants to avoid in raised beds

Do not plant trees, large shrubs, or perennials with deep or spreading root systems in raised beds. Asparagus, rhubarb, and artichokes are perennials that need to stay in place for years and will eventually break through the bed's sides or bottom. Corn, sunflowers, and other tall plants shade everything around them and are better grown in a separate area or at the north edge of your garden so they don't block sun from shorter plants.

Potatoes can be grown in raised beds, but they need 12 to 18 inches of loose soil and will deplete nutrients quickly. If you grow them, plan to refill the bed with fresh compost the following year. Squash and pumpkins sprawl and take up too much space unless your bed is at least 4 feet by 8 feet and you train them up a sturdy trellis.

Frequently Asked Questions

Can I plant tomatoes and lettuce in the same raised bed?

Yes. Plant lettuce in spring, harvest it before tomato transplants go in (late May or early June depending on your location), then plant tomatoes in the same space. Lettuce grows in cool weather and is done before tomatoes need the full bed. You can also plant lettuce again in late summer after you remove tomato plants in fall.

How deep does a raised bed need to be for vegetables?

Shallow-rooted crops like lettuce and herbs need 8 to 10 inches. Root vegetables and tomatoes need 12 to 18 inches. If you are building a new bed and want flexibility, aim for 18 inches deep. You can grow shallow-rooted plants in deep soil, but you cannot grow deep-rooted plants in shallow soil.

Should I use garden soil or potting mix in a raised bed?

Use a mix of topsoil, compost, and peat moss or coconut coir. Garden soil compacts over time and drains poorly in a raised bed. Potting mix alone is too expensive for a large bed and drains too fast. A 50-30-20 blend (topsoil, compost, peat moss) works well and costs less than filling the entire bed with either one alone.

Can I grow the same vegetables in the same raised bed every year?

You can, but rotating crops prevents disease and pest buildup. If you grew tomatoes in one bed this year, plant beans or lettuce there next year. Tomatoes, peppers, and eggplants are in the same plant family and share pests and diseases, so avoid planting them in the same spot two years in a row.

What vegetables grow in partial shade?

Lettuce, spinach, arugula, parsley, and chives tolerate 3 to 4 hours of direct sun and can be planted near a fence or building. Tomatoes, peppers, and most herbs need 6 to 8 hours of direct sun. Root vegetables like carrots and beets need at least 5 to 6 hours but can handle slightly less sun than heat-loving crops.