Reading a seed packet
Decode the numbers and symbols on seed packets so you can sow at the right time, depth, and spacing for your climate.
8 min · beginner
You will learn
- Interpret days-to-maturity relative to your frost dates
- Match sowing timing to hardiness ratings on the packet
- Apply correct depth and spacing from packet instructions
Days to maturity
The days-to-maturity figure estimates time from sowing or transplanting to harvest under ideal conditions. For crops started indoors, the packet often lists days from transplant, not from seed. Cool weather slows growth; heat can speed or stress plants depending on the crop. Count backward from your first fall frost or forward from last frost to see if the variety fits your season.
Hardiness and sowing windows
Packets indicate whether a crop tolerates frost, needs warm soil, or performs best in cool weather. Hardy crops like peas and spinach can be sown weeks before last frost. Tender crops like beans and squash wait until soil warms. University of Minnesota Extension planting guides list recommended sowing and transplant dates keyed to local frost dates rather than calendar dates alone.
Sowing depth and spacing
Seed size generally dictates depth: plant at a depth of two to three times the seed's largest dimension. Fine seeds like lettuce are barely covered; large seeds like beans go an inch or more deep. Row spacing tells you how far apart to make sowing lines; plant spacing is the final distance between individuals after thinning. Follow both numbers to avoid overcrowding.
Other useful packet information
Packets may note whether seed is open-pollinated, heirloom, or hybrid. University of Minnesota Extension explains that open-pollinated seed can produce plants similar to the parents, while hybrid seed produces variable offspring if saved. Treated, organic, and pelleted labels describe processing that affects handling and sowing. Use lot and packed-for dates when deciding whether to run a germination test on older seed.