When should I sow my flower and vegetable seeds indoors?

Question:

When should I sow my flower and vegetable seeds indoors?

Answer:

The growth rate of the seedlings and the outdoor planting date determine when to sow seeds indoors.  The crop time (number of weeks from sowing to planting outdoors) for several popular flowers and vegetables are as follows: 10 to 12 weeks - geranium; 8 to 10 weeks - petunia and impatiens; 6 to 8 weeks - marigold, pepper, and eggplant; 5 to 7 weeks - tomato, cabbage, broccoli, and cauliflower; 3 to 4 weeks - cucumber, watermelon, muskmelon, and squash.