When should I start seeds indoors?
Count backward from your last frost date using the seed packet's weeks-to-transplant number — most tomatoes and peppers go in 6–8 weeks before last frost.
The seed packet usually tells you what you need: 'start indoors 6–8 weeks before last frost.' Your last frost date is the anchor. Count backward from that date — if your last frost is typically around the end of April and you're growing tomatoes, you'd start seeds in early to mid-March. Starting too early is a more common mistake than starting late.
Tomatoes and peppers should go in 6–8 weeks before your last frost. Basil does well at 4–6 weeks. Cucumbers, squash, and melons need only 3–4 weeks — they grow fast and don't like sitting in pots long. Brassicas like broccoli, kale, and cabbage can go in 6–8 weeks before last frost for a spring crop, or 8–10 weeks before your first fall frost for a fall crop.
Plants started too early get root-bound in their cells, develop woody stems before they go outside, and often struggle to adapt to outdoor conditions. A six-week tomato transplant that is stocky and deep green will typically outperform a ten-week transplant that has been sitting in a four-inch pot for too long.
After starting, seedlings need warmth for germination (a heat mat under the tray helps with peppers and tomatoes, which prefer 75–85°F soil to germinate) and then bright light as soon as sprouts appear. Moving to bright light within 12 hours of emergence prevents legginess from the start.
- TomatoThe warm-season anchor of the summer garden.
- PepperA tropical perennial grown as an annual — patient, slow, and particular about warmth.
- BasilThe summer companion — to tomatoes, to pasta, and to the gardener with a south-facing window.
- CucumberA thirsty vine that wants warm soil, steady water, and something to climb.
- KaleThe cold-weather workhorse that improves when everything else quits.
- Bird DamageBerries pecked or missing, seeds scratched from beds, and seedlings dislodged — birds feeding on ripe fruit, seeds, or soil grubs.
- Brown Marmorated Stink BugSunken, corky dimples on fruit and pods caused by a mottled brown shield bug feeding through the skin.
- Cabbage MaggotBrassica transplants wilting and dying as white maggots tunnel through roots at or below the soil line.
- Carrot Rust FlyRusty tunnels through carrot and parsnip roots made by small white maggots feeding inside the root.
- ClubrootBrassica plants wilt and yellow despite watering; roots show club-shaped swellings when dug.
- Why are my seedlings tall, pale, and floppy?Seedlings stretch toward inadequate light — the fix is moving them closer to the light source, not giving them more hours of light.
- How do I harden off seedlings before transplanting?Gradually expose indoor seedlings to outdoor conditions over 7–10 days, starting with an hour of shade and building up to full sun and overnight temperatures before planting.
- My transplants look wilted and sad after planting — is this normal?Some wilting and leaf drop in the first few days after transplanting is normal; if a plant is still wilting after a week and well-watered, the roots may have been damaged.
- What is a last frost date and how do I actually use it?Your last frost date is the average date of the final freezing night in spring — it's a probability, not a guarantee, and smart planting adds a buffer of 1–2 weeks beyond it for cold-sensitive crops.