Most seed packets will give you some idea of when you can plant the seeds directly in the ground, but knowing when to plant seeds cannot be determined solely by looking at a calender. Weather can be unpredictable and your garden soil will not be ready to plant on a schedule. Soil often needs a few weeks at the start of the season, to warm up and dry out a bit. Seeds planted in cold, wet soil will simply rot. So here are two ways to tell if your soil is ready to be worked.
- The Shovel Test: The simplest test is whether the soil sticks to your tools. If you put your shovel in the ground and it comes up clumped with mud, you'll have to wait.
- The Crumble Test: A more accurate test is the crumble method. Form a handful of soil into a ball in your hand. If it crumbles apart with a slight touch of your finger, it's time to plant. If it holds together and requires pressure to break apart, it is still too wet. (And if it won't form a ball, you can plant, but you'll need to water.)
This is a good rule of thumb for when you are preparing potting soil for indoor starts too. Water the potting soil to crumble consistency, before you will your pots.