The timing, plainly

How many weeks before last frost should you start seeds?

Count backward from your last expected frost date — and let the seed packet, not the calendar, set the number. It’s commonly a few to several weeks indoors, but it genuinely varies by crop: some want a long head start, while others resent being started early and turn leggy and rootbound before the ground is ready. Two things trip people up. The first is starting too soon, out of enthusiasm, the moment the seed catalogs arrive. The second is anchoring to a fixed date instead of your actual last-frost date and soil, which shift by region and year. Find your frost date, read the weeks-before number on each packet, and count back from there.

⏱ The window: Count back from your last frost date — check each packet

Start-indoors timing swings by crop, so the packet’s weeks-before number is the real instruction. Start too early and seedlings outgrow the season before it’s safe to plant them out.

Where it sits in the year

Ordered from this month — this is the shape of it on a timeline.

JanLook up your local last-frost date
JanRead the weeks-before-frost number on each seed packet
FebStart seeds indoors — counted back from frost, not the calendar
MarHarden off, then transplant once frost risk has passed
How many weeks before last frost do I start seeds?

It varies by crop — commonly a few to several weeks — so read the number on each packet rather than averaging them into one date. Long-season plants and quick growers want very different head starts.

Is it too late to start this year?

Often not. Count forward from today to your frost date and check the packet’s days-to-maturity — many warm-season crops still fit, and some fast growers can be sown straight into the ground.

Why did my seedlings get leggy?

Usually too early a start or too little light, so they stretch before it’s safe to plant out. Matching the start date to the packet and your own frost date is what avoids the stretch.

The date is the easy part. Remembering is the product.

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