Seed Packet Coverage Calculator

How to Plan a Seed Order

• Choose the crop you are sowing into straight open rows.
• Add up the total row feet you plan to sow this season.
• Enter what a packet costs where you actually buy seed.
• Read the packets to put in the basket at the checkout.
• Note the seed count so you can share or store the surplus.
• For succession crops, split the row and resow fortnightly.
• Check the packet's packed-for date before trusting coverage.
• Sow small seed thin — the extra seed is for thinning, not for depth.

How Packet Coverage Is Worked Out

Worked Example: Twenty Feet of Carrots

• You plan a twenty-foot carrot run in the raised bed this spring.
• A carrot packet covers about one hundred feet of row at a thin steady sow.
• Packets: twenty divided by one hundred, rounded up, is one single packet.
• That one packet holds roughly eight hundred tiny seeds, far more than the row needs.
• At three dollars a packet, the whole line costs just three.
• Sow the twenty feet thin in one continuous band, not a hole-per-seed drill.
• Thin to two-inch spacing when the first feathery tops touch — the surplus is your insurance.
• Label and store the leftover seed cool and dry for next season's succession rows.

Coverage and Seed Count by Crop

Key Terms

Row coverage

The feet of row a packet is printed to sow at the crop's correct thin-sowing rate.

Thinning

Pulling surplus seedlings to leave proper spacing; small-seed crops are oversown on purpose for it.

Cluster seed

A beet 'seed' that is actually a fruit of several embryos, sprouting a tight group that must be thinned.

Succession sowing

Replanting a short row every couple of weeks instead of the whole length at once.

Germination rate

The percent of seed expected to sprout, printed on fresh packets and the hidden variable in coverage.

What This Means for the Seed Rack

• Leftover seed is the norm, not waste — small-seeded crops are packed generous because thin sowing and patchy germination eat the margin, which makes year two's succession free.
• Check the packed-for date every time: stored alliums and parsnips fall off a cliff after a year, while beans and tomatoes stay viable for several, so coverage math rots with the packet.
• Buy by row footage, not enthusiasm — the market-stall packet doubles your bean cost for seed you will never sow, and the carrot under-buy is one envelope, not a plan.
• For succession crops like radish and spinach, divide the row into segments sown a fortnight apart; staggered stations put staggered harvests on the table.
• If a crop needs pinpoint spacing — onions from seed, early beans against a frost date — draw rates from the germination calculator's viability figures instead.

Common Mistakes & Fixes

• Sowing a whole carrot packet into a ten-foot row in one fat band, then fighting a mat of seedlings at thinning time.
• Assuming a five-year-old jar germinates like a fresh packet and wondering why half the row never came up.
• Buying beans by the packet for a long run and stopping mid-row, because fifteen feet per envelope adds up fast.
• Thinning beets once, leaving the cluster siblings, and harvesting a fistful of competition-sized crowns.
• Sowing the entire successional row on one day, so radishes all hit harvestable the same week and go woody unnoticed.

When to Use This (and When Not To)

Seed Packet Coverage Calculator: Frequently Asked Questions