I received a comment from Tim today asking: When do you start vegetable seeds indoors? Beginning of March or earlier?
Thanks for the question, Tim. The answer is, “that all depends”. Factors which determine when to start your seeds indoors are your USDA Hardiness Zone, your last frost date, and the kind of vegetable or flower you’re growing.
For instance, I live in Zone 6b with a potential last frost date of May 15th. If I want to grow early season vegetables like spinach, then yes, I should start now and transplant the seedlings to my garden at the beginning of April. If however, I’m growing tomatoes (which love heat), then I would start them by mid-March, 8 weeks from my last frost date.
I would also recommend an excellent book on the subject: The New Organic Grower: A Master’s Manual of Tools and Techniques for the Home and Market Gardener (A gardener’s supply book). 
Eliot Coleman provides fabulous advice on starting seeds early, transplanting, using the correct pots or soil blocks and when to place them in your garden. It’s an indispensable reference which every gardener should own.
I hope that helps you, Tim!