Start with soil, not seeds

Before you plant anything, your raised bed needs to be filled with the right soil mix. Most gardeners use a combination of topsoil, compost, and peat moss or coconut coir in roughly equal parts. This blend drains well, holds nutrients, and gives seeds and seedlings room to grow without compacting.

Fill your bed to within 2 inches of the top. The soil will settle over the first few weeks, so don't worry if it looks a bit high at first. Water the soil thoroughly before planting — it should be moist but not soggy, like a wrung-out sponge. Let it sit for a day or two if you can; this helps the soil settle and makes it easier to work with.

Key Takeaways

  • Fill your raised bed with a mix of topsoil, compost, and peat moss or coconut coir in roughly equal amounts, then water it well before planting.
  • Plant seeds or transplants at the depth marked on the seed packet or plant tag, spacing them according to the instructions on the packet.
  • Water gently after planting so the soil settles around seeds or roots without washing them away or creating air pockets.
  • Most vegetables and flowers need 6 to 8 hours of direct sunlight daily, so position your bed where it gets afternoon sun if possible.
  • Mark where you planted each variety with a label or stake so you remember what is where as plants grow.

Decide whether to plant seeds or transplants

You have two routes: start from seed, or buy seedlings (also called transplants) from a garden center and plant those. Seeds are cheaper and give you more variety, but they take longer to produce a harvest — usually 6 to 12 weeks depending on the crop. Transplants are ready to go into the ground and will produce food or flowers much sooner, often in 3 to 8 weeks.

If you are new to gardening, transplants are the easier choice. Lettuce, tomatoes, peppers, basil, and zucchini all do well as transplants. If you want to start from seed, choose fast-growing crops like radishes, beans, or carrots — they are harder to kill and show results quickly. Check the seed packet for the number of days to maturity; anything under 60 days is a good beginner crop.

Plant at the right depth and spacing

The seed packet or plant tag tells you exactly how deep to plant and how far apart. Read it before you dig. As a general rule, seeds go as deep as they are wide — a tiny lettuce seed goes barely under the soil surface, while a bean seed goes about an inch down. Transplants go in at the same depth they were growing in their pot; look for the soil line on the stem and plant to that mark.

Spacing matters because crowded plants compete for water, nutrients, and light. A tomato transplant might need 24 inches between plants, while lettuce needs only 6 inches. If you plant too close, you will have weak plants and more disease. If you are unsure, space plants a bit farther apart than the packet says — you can always thin them later if they look sparse.

Make a small hole with your finger or a trowel, place the seed or transplant in it, and gently press soil around it. For transplants, firm the soil so there are no air pockets around the roots. For seeds, cover them and pat the soil gently so it makes contact with the seed.

Water carefully after planting

Water when ready after planting, but gently. Use a watering can with a rose (the sprinkler head) or a hose on a low setting. The goal is to settle the soil around seeds or roots without washing them away or creating air gaps. The soil should be moist to a depth of about 3 inches — deep enough to reach the roots of transplants or to keep seeds from drying out.

For the first week or two, check the soil every day. In warm weather, the top inch may dry out quickly. If it does, water again. Once plants are established and growing, you can usually water less often — most vegetables need about 1 inch of water per week, either from rain or from you. Water in the morning if you can; it gives foliage time to dry and reduces disease.

Position your bed for sunlight

Most vegetables and flowering plants need 6 to 8 hours of direct sunlight daily. Leafy greens like lettuce and spinach can manage with 4 to 6 hours. Tomatoes, peppers, and squash want the full 8 hours or more. Before you plant, watch your yard through the day and note where the sun hits longest.

If your bed is in a spot that gets afternoon shade, that is often better than morning shade — afternoon sun is stronger and helps prevent fungal diseases that thrive in damp morning shade. If you have a choice between a spot with 6 hours of morning sun and one with 6 hours of afternoon sun, choose the afternoon spot.

Label what you planted and when

Write the plant name and planting date on a stake, popsicle stick, or garden label and push it into the soil next to each plant or row. This sounds obvious, but it is straightforward to forget what you planted after a few weeks, especially if you planted multiple varieties of the same crop. Labels also help you track which plants are doing well in your conditions and which are struggling.

If you planted from seed, note the expected harvest date on the label too. A radish planted on May 1 with a 30-day maturity will be ready around June 1. Knowing this helps you plan succession plantings — planting a new batch of seeds every two weeks so you have a steady harvest instead of everything ripening at once.

Common mistakes to avoid

Planting too early in spring is the most common mistake. Soil that is cold and wet will rot seeds before they sprout. Wait until the soil is warm — at least 50°F for cool-season crops like lettuce, and 60°F or higher for warm-season crops like tomatoes and peppers. A soil thermometer costs a few dollars and takes the guesswork out.

Planting too deep is the second mistake. Seeds especially need light and warmth to sprout. A tomato seed buried half an inch too deep may never germinate. Transplants planted too deep can rot at the stem. Read the packet and follow it exactly.

Overcrowding is the third. It is tempting to plant close together to fill the bed, but crowded plants are weak plants. Stick to the spacing on the packet. Your bed will look sparse for a few weeks, but it will fill in as plants grow.

Frequently Asked Questions

Can I plant seeds and transplants in the same bed?

Yes. Plant transplants where you want them, then sow seeds in the gaps. This works well for mixing fast-growing crops (seeds) with slower ones (transplants). For example, plant tomato transplants 24 inches apart, then sow radish seeds in the spaces between them. The radishes will be ready to harvest before the tomatoes need the room.

How long before I see sprouts from seeds?

Most vegetable seeds sprout in 5 to 14 days, depending on the crop and soil temperature. Beans and squash are fast (3 to 7 days). Carrots and parsnips are slow (14 to 21 days). Warmer soil speeds germination; cold soil slows it. Keep the soil moist but not waterlogged while you wait.

What if I plant and nothing comes up?

Seeds fail for three reasons: they were planted too deep, the soil was too cold or too wet, or the seeds were old or damaged. If nothing sprouts after three weeks, replant. This time, plant shallower and wait for warmer soil. If you used old seed packets, buy fresh seed — seeds older than a year have lower germination rates.

Do I need to fertilize right after planting?

Not when ready. A good compost-rich soil mix has enough nutrients to get seedlings started. Once plants are growing actively (usually 3 to 4 weeks after planting), you can feed them with a balanced fertilizer every two to three weeks. Follow the package directions for amount and frequency.

Can I plant in a raised bed in fall?

Yes. Cool-season crops like lettuce, spinach, kale, and broccoli actually prefer fall planting. Plant them 8 to 10 weeks before your first frost date so they have time to mature before cold weather stops growth. Use the same planting method as spring — just adjust the timing to your local frost date.