How do you know when to plant? Well, there are no guarantees, but if you let nature tell you when it's safe to plant seeds or put your plants out, you're probably on the right track. Nature sends certain signals that will let gardeners know how the weather and climate are progressing. There's a science devoted to this, called phenology.
Phenology is the study of the timing of recurring biological phenomena and their relationship to the weather. It is useful to gardeners, as a guide for when to plant. Weather can vary from year to year, but you can let the plants and animals tell you when it's time to start seeds. For instance, plant your peas when the forsythia blooms. It's no guarantee that you won't lose a few plants to a late frost, but phenology is a good guideline to keep you in the ballpark. You can even use it to be pro-active against pests.
Here's some basic phenological gardening advice.
|Peas||... forsythia & daffodils blooms|
|Plant potatoes||... the first dandelion blooms or the shadbush flowers|
|... the shadbush flowers|
|Beets, carrots, cole crops, lettuce and spinach||... lilac is in first leaf|
|Beans, cucs and squash||... lilac is in full bloom|
|Tomatoes||... lily-of-the-valley are in full bloom|
|Corn||... apple blossoms start to fall|
|Cool season flowers (pansies, snapdragons...)||... aspen and chokecherry trees leaf out|
|Eastern tent caterpillars to hatch||... crab apples start to bloom|
|Gypsy moths hatch||... the shadbush flowers|
|Squash vine borer eggs are laid||... when chicory flowers|
|Mexican bean beetle larvae hatch||... when foxglove flowers open.|
|Japanese beetles arrive||... when morning glory vines start to climb|