There are many reasons why it’s smart to start seeds indoors:
Many plants have long growing seasons and they won’t flower or fruit unless they get a head start inside.
Even if plants don’t need to be started indoors, they’ll grow larger and bloom longer if started early.
Plants with fine seeds are protected them from harsh weather.
You have a lot more control over weeds, insects, and disease.
Of course, you can always buy plants in the spring from a nursery that started them indoors
Before planting, check to see if your type of seed needs any special handling.
Some seeds sprout easier if you soak them before planting. Don’t soak them too long, however, because some seeds can become waterlogged and will decay.
Some seeds with hard outer shells will sprout faster if their shell is slightly broken. Use a knife, file or sandpaper to break the surface gently, without breaking the plant embryo inside.
A few annuals that must be started indoors include begonia, coleus, geranium, impatiens, some marigolds, petunia, pansy and verbena.
Some vegetables that need longer growing seasons in order to produce include broccoli, brussels sprouts, cabbage, cauliflower, celery, peppers, and tomatoes.
Start seeds about six to eight weeks before you expect to take them outside.