Ready, Set, Sow! Answers to Seed Starting FAQs

Answers to Frequently Asked Questions About Starting Seeds Indoors

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A seed-starting kit like GrowEase makes vigorous, healthy seedlings easy.

Many experienced outdoor gardeners hesitate to start seeds indoors. But it's one of the most rewarding parts—hands in soil during dark winter days, watching lifeless seeds sprout and grow. Here are answers to hundreds of seed-starting questions.

Why Start Seeds Indoors?

Three pepper varieties for the price of one!

Reasons: access to hundreds of varieties (vs. dozen at garden centers), save money (packet costs dollars, contains dozen+ seeds vs. single plant cost), beat winter blues, rewarding to grow from seed to harvest.

Easiest Seeds to Start Indoors?

Zinnias are among easiest flowers from seed.

Begin with: tomato, pepper, basil, zinnia, marigold, cosmos. Germinate readily, grow fast. Then try challenging plants.

When to Sow Seeds?

Most packets include sowing instructions.

Timing is everything. Goal: ideal transplant size at proper garden time. Depends on: last frost date, cool/warm preference, germination/growth speed. Packets say "sow indoors 6 weeks before last frost." Determine your average last frost, mark calendar, count back weekly.

How to Know Last Frost Date?

Create planting calendar by counting back from last frost.

Ask experienced neighbor, local Master Gardener (Cooperative Extension), or garden center staff. Actual last frost varies yearly; average is approximation but good starting point.

Windowsill or Grow Lights?

Sad seedlings reaching for light on windowsill.

Possible on sunny windowsill, but grow lights give much better results. Early spring sun isn't intense, days are short. Windowsill seedlings become long, weak, bending toward light. Under consistent fluorescent lights: strong, stocky stems that transplant better.

Can I Use Garden Soil?

Seed-starting mixes are well-drained and disease-free.

Garden soil drains poorly in small trays and harbors disease organisms. Use lightweight seed-starting mix (e.g., Germinating Mix): drains freely, retains moisture for roots, free of fungi and pathogens.

What Type of Pot?

Seed-starting systems designed for healthy growth.

Any container with drainage works, but specialized pots/trays provide optimal conditions: start many seeds in small space, drain freely to prevent rot. Biodegradable (Cowpots) or reusable trays. Self-watering all-in-one systems are convenient and foolproof.

How Deep to Plant?

Basil, pepper, zinnia seeds: different sizes, different depths.

Packets usually specify. Rule: sow 2-3x seed width deep. Don't plant too deep—seed has limited food; too deep = runs out before reaching light. Some need light to germinate—sow on surface.

Top or Bottom Watering?

Self-watering starters take guesswork out.

Bottom watering preferable: keeps surface drier, prevents disease. For small/surface seeds, top misting keeps surface moist. Self-watering systems (GrowEase) use wicking fabric for steady, perfect moisture—fill reservoir, no over/under-watering.

When to Remove Greenhouse Cover?

Remove cover at first sprout.

Cover holds moisture for germination. Remove at first tiny sprout for air circulation, minimizing disease.

How Close Should Lights Be?

Keep lights 4-6 inches above seedlings.

Few inches from tops promotes strong, stocky growth. Adjustable lights raise as seedlings grow.

Leave Lights On All the Time?

Timer makes proper light easy.

14-16 hours daily best. Need darkness period to rest and prepare for active growth. Automatic timer makes it easy.

Do I Need to Thin Seedlings?

Thin to one per cell.

Few weeks after germination, crowding occurs. Choose strongest, snip others at soil line. Separating damages roots, sets back growth. Hardest part for most gardeners.

When to Start Fertilizing?

"True leaves" resemble mature plant leaves.

First set = cotyledons (food storage). Second set = true leaves. Begin fertilizing at 1-2 inches tall or second true leaf set.

When to Transplant to Larger Pots?

Time to transplant before roots crowd.

~1 month after sowing or 4" tall: gently remove one. If roots filling space, transplant to larger pot. Don't wait—crowding stunts growth, complicates recovery.

What is "Hardening Off"?

Acclimate seedlings before garden planting.

Hardening off = acclimating to outdoor conditions. Indoors: coddled with perfect light, moisture, nutrients. Outdoors: fluctuating temps, light, moisture, wind. Week before transplant: protected spot outdoors (part shade, no wind) few hours, bring in at night. Gradually increase sun/wind over 7-10 days. Cold frame ideal.

What Went Wrong?

Even experienced starters have problems. Symptoms and causes:

• Poor germination: insufficient time, wet/cold soil (rot), dry soil, soil dried after germination, old/improperly stored seed.
• Damping off: seedlings keel over at soil line—soil-borne fungi. No cure. Restart with clean containers, sterile mix. Dry surface between waterings, fan for air circulation. Sterilize containers in 10% bleach.
• Mold/algae: fuzzy white or slimy green—too wet. Dry slightly, small fan for air.
• Pale, stretched, weak stems: "Leggy" = inadequate light (intensity/duration). Use grow lights, few inches above, 14-16 hours. Also caused by too-warm temps, overcrowding, inadequate fertilizing.
• Discolored leaves: pale green, yellowish, purple cast = nutrient need. Fertilize at 1-2 inches or second true leaves. Half-strength water-soluble weekly, then full strength.