That is without question the worst table that I've ever seen. Here is my own personal table:

Onions - January (already started them)

Broccoli, Cauliflower, Brussel Sprouts - late February

Tomatoes, Peppers, Snow Peas - late March

Corn, Okra, Cucumbers, Lettuce (direct sow) - late April

Watermelons, Cantaloupes, Summer Squash, Beans, Potatoes (and sometimes Sunflowers) - direct sow mid to late May