Common Questions

A bed in a spot with six or more hours of sun, enough soil to fill it properly, and plants or seeds. Everything else is an upgrade. Buying in that order is the single biggest thing that separates a productive first year from a discouraging one.

Ten to twelve inches suits most vegetables, including tomatoes, peppers, beans and brassicas. Go to 17 inches or more if you want carrots, parsnips or potatoes. Below 8 inches you are limited to salad crops and herbs.

Four feet if you can reach it from both sides, or 2 to 3 feet against a wall. The measurement is set by your reach rather than your space: you must be able to work the middle without stepping in, because compaction undoes the point of a raised bed.

At 12 inches deep, 32 cubic feet -- about 1.2 cubic yards, or sixteen 2-cubic-foot bags. At 17 inches, roughly 45 cubic feet. Multiply length x width x depth in feet, and add about 10 percent for settling.

Fill everything below the top 10 to 12 inches with material you can get free -- logs, branches, leaves, grass clippings, straw, spent potting soil -- and buy good growing mix only for that top layer, where nearly all the roots are. On a deep bed that can halve the bagged-mix cost.

No. It is a persistent myth. A coarse layer under finer soil creates a perched water table: water will not cross the texture boundary until the soil above is saturated, so the root zone ends up wetter rather than better drained.

Yes. Garden bed steel is zinc-coated, zinc is a plant micronutrient, and the coating is stable at the near-neutral pH a vegetable bed runs at. The material that genuinely warrants caution in a food bed is older pressure-treated timber, not coated steel.

The soil within a few inches of a sun-facing panel runs warmer than the middle of the bed. In cool and temperate climates that is an advantage -- the bed warms earlier in spring. In hot climates, mulch the surface and plant a few inches in from the hottest side.

Only for specific problems: poor drainage, compacted or stony soil, possible contamination, or a need for height. If your existing soil is decent, in-ground growing plus regular compost produces just as well for a fraction of the cost and less watering.

Roughly two to three parts browns to one part greens by volume. Browns are dry carbon-rich material -- leaves, cardboard, straw. Greens are wet nitrogen-rich material -- kitchen scraps, grass clippings, coffee grounds. A handful of browns per bucket of scraps is close enough.

Almost always too many greens and not enough air. Wet nitrogen-rich material packs down, oxygen runs out, and anaerobic bacteria take over. Add plenty of dry browns, turn it thoroughly, and it usually recovers within a few days.

Meat, fish, dairy, oils and cooked food, because home piles do not get hot enough to handle them and they attract rodents. Also cat and dog waste, diseased plant material, and weeds that have set seed unless your pile genuinely heats.

Red wigglers, Eisenia fetida. They live in decaying organic matter near the surface, which is what a bin provides. Garden earthworms and nightcrawlers are deep-soil burrowers and will try to escape a bin or die in it.

Count back from your last expected frost date: 6 to 8 weeks for tomatoes, 8 to 10 for peppers and eggplants, 4 to 6 for brassicas, and 3 to 4 for cucumbers and squash. Starting earlier produces root-bound seedlings that transplant worse, not better.

In practice, yes. A windowsill in late winter gives light from one side and not much of it, so seedlings stretch and stay weak. An LED strip 2 to 4 inches above the tray, run 14 to 16 hours a day, is the cheapest and most effective fix in seed starting.

Only for warm-season crops. Peppers, eggplants, tomatoes, cucumbers and squash germinate far faster with warm soil. Lettuce, brassicas and peas do not need it, and lettuce germination is actually inhibited by warm soil. Take the tray off the mat once seeds are up.

A 6 x 8 ft kit handles seed starting, hardening off and a few crops grown to maturity. If you want to raise seedlings and also grow tomatoes and cucumbers under cover, 8 x 10 ft is a more realistic minimum. Buying too small is the most common regret in this category.

Hardy crops, yes -- spinach, mache, kale, winter lettuces and chard. An unheated greenhouse holds a few degrees over outside and keeps wind and rain off. Tomatoes, peppers and basil need warmth and light levels that winter does not supply.

For most home gardens, twin-wall polycarbonate. It insulates far better than single glazing, diffuses light so seedlings do not scorch, and does not shatter. Glass transmits more light and looks better, which makes it a choice for sheltered, ornamental settings.

No, and we say so on every relevant page. We run no lab and no trial garden. Recommendations come from published specifications, independent sources and buyer feedback, weighed against stated criteria. The full method is on the how we choose page.