"When is the Best Time to Start Seeds? A Quick Guide for Seed Starting Dates"

Utah has a highly variable climate, meaning that climactic conditions can change drastically within short distance. For example, the number of frost-free growing days in Salt Lake City averages 210, while Park City, a 20-minute drive from Salt Lake City, is limited to 108 frost-free days. This high variability and broad range of USDA hardiness zones can make calculating seed starting dates for an area complicated.

I have taken the guesswork out of the process for you so that you can start seeds according to your zone. Simply find your zone (you can do that here), find the vegetable or flower you want to plant on the guide and find the suggested sow date. Please note that these are suggested dates based on average temperatures; if your microclimate varies from these dates, you can adjust accordingly. Dates are calculated assuming you are planting on the average last frost date for each zone. Planting out cold hardy crops a few weeks prior to this date will also require you to adjust and move the sow date back by the number of days you are planting preceding the last frost date.

Crops listed are those that are most common. If you have a unique plant you can find the sow date by looking on the seed packet for the number of weeks recommended for sowing prior to transplant. The number of weeks and correlating dates is also listed on the guide so you can easily figure out practically any sow date for any seed.

There are several crops that do best direct sown into the garden and should not be transplanted. These include all vegetables with a taproot such as beets, carrots, turnips, and radish, as well as potatoes. Beans, peas, corn and squashes can be planted as transplants but often establish better when direct sown. Flowers that do best direct sown include bells of Ireland, sunflower, cosmos, phlox, and sweet pea.

Vegetable calendar

Flower calendar

Calendars can be viewed and printed here.