I thought this might be of use. I got it in an email from John Scheepers.

Eight-week General Seed-Starting Timetable

Horticultural Zones 9 & 10: Start seeds indoors now.

Horticultural Zone 8: Start seeds indoors in early February.

Horticultural Zone 7: Start seeds indoors in mid February.

Horticultural Zone 6: Start seeds indoors in late February.

Horticultural Zone 5: Start seeds indoors in early March.

Horticultural Zones 1-4: Start seeds indoors in mid to late March.

There are vegetables, herbs and flowers that require more or less time than the standard eight weeks. Here are the seed starting schedules for them:

Vegetable/Herb Seed-Starting Timetable

Four Weeks: Melons, Bitter Melon and Cucuzzi Edible Gourds.

Six Weeks: Asparagus, Fennel, Onions, Rhubarb, Shallots, Tomatillos, Basil and St. John's Wort.

Eight Weeks: Eggplant, Tomatoes, Chiles, Sweet Peppers, Chives, Sage, Stevia and Thyme.

Nine Weeks: Broccoli, Cabbage and Kohlrabi (transplant out four weeks before the last frost date).

Ten Weeks: Celery, Celeriac, Jicama and Lemongrass.

Eleven Weeks: Leeks, Artichokes and Cauliflower (transplant out four weeks before the last frost date).

Twelve Weeks: Cardoons and Brussels Sprouts.

Sixteen Weeks: Strawberries (for first year crop) and Rosemary.

Flower Seed-Starting Timetable

Five Weeks: Alyssum.

Six Weeks: Cutting Ageratum, China Asters, Celosia, Cleome, Coleus, Nepeta Catmint, Echinacea, Euphorbia, Forget-Me-Nots, Dahlia, Nicotiana, Scabiosa, Snapdragons and Thunbergia.

Eight Weeks: Baby�s Breath, Black-Eyed Susans, Milkweed, Coreopsis, Gaillardia, Globe Amaranth, Helichrysum, Hibiscus, Hollyhock, Heuchera, Nigella, Platycodon, Statice and Yarrow.

Ten Weeks: Dianthus, Digitalis, Lobelia and Heliotrope .

Twelve Weeks: Datura, Salvia and Viola.