Seed packets pack a surprising amount of planning information into a few lines of small print. Misreading any one of them is a common reason first plantings fail.
Days to maturity
This counts from either direct-sowing or transplanting outdoors — not from the day you started seeds indoors. A tomato listed at "75 days" means 75 days after it goes into the ground as a transplant, not 75 days from seed.
Sowing depth and spacing
Depth matters more than most gardeners assume: seeds sown too deep may never reach the surface, while seeds sown too shallow dry out before germinating. As a rule of thumb, plant at a depth of roughly twice the seed's diameter.
"Days to germination" vs. "days to maturity"
These are frequently confused. Germination time tells you how long before you see a seedling at all; maturity tells you how long until harvest. A packet listing "7–14 days germination, 60 days maturity" means roughly 46–53 additional days of growing after the seedling emerges.
Hardiness zone map
The small map on the back is a planting-date guide, not a growing guarantee. It shows recommended outdoor planting windows by region — cross-reference it with your specific USDA zone and average frost dates rather than reading it as a strict rule.
Sun Exposure Codes
"Full sun," "partial shade," and "full shade" on a packet refer to actual measured hours of direct light, not general brightness — full sun means 6+ hours of direct sunlight daily, partial shade means 3-6 hours, and full shade means less than 3. A spot that feels bright because it's open to the sky but faces north can still fail a "full sun" plant if it never receives direct, unobstructed sunlight for the required hours.
Seed Treatment Notes: What "Treated" Actually Means
Packets marked "treated" have been coated with a fungicide to improve germination rates in cold, wet soil — useful for very early spring sowing but worth knowing before handling seeds without gloves or feeding them to any animals, since the coating is not food-safe. Untreated or organic-certified seeds skip this step and may show slightly lower germination in poor conditions, a tradeoff worth understanding rather than assuming treated seeds are simply "better."