At This Time: Late March/Early April
Plant These: Leaf lettuce, onion sets, asparagus crowns, cilantro, parsley, potatoes, radishes, peas, collard greens, mustard greens
And Remember: Pay attention to spacing and volume. A lettuce seed packet, for instance, might have more than 200 seeds. “It’s a common pitfall to open a packet and dump all the seeds in,” Judy Elliott, senior education specialist at Denver Urban Gardens says—which means they’ll all mature at once. For veggies that mature quickly, like lettuce and peas, use 10 or so seeds at a time, and no more than two to a hole (double seeds can help you get a head start on germination), at intervals designated on the packet. (While you might be tempted to assume you should start these seeds inside, Elliott says you should plant them in the ground. Just consult the weather­—and don’t kick off your garden in a snowstorm.)

At This Time: Mid- To Late-April
Plant These: Carrots; transplants of cabbage, broccoli, cauliflower
And Remember: “Hardening off” your transplant plants is important: Expose them to increasing amounts of sunlight during the course of a week, starting with an hour in the shade and adding a few hours each day. Then go ahead and give them a home in the ground.

“Once your plants are growing, you want to make sure your soil stays soft” so the water and nutrients can penetrate the soil, Elliott says. “One thing that helps is mulching [try straw mulch, not bark]; after the crops are up, pull the mulch back from the plant and very lightly scratch the soil surface around the plant so water can penetrate deeper, then push the mulch back to the plant.” Water the soil only—not the leaves—with a slow spray.

At This Time:  First week of May
Plant These: Culinary sage, zucchini, summer squash, winter squash, pumpkin, corn, sweet basil, cucumber, melon
And Remember: Consider putting herbs like culinary sage, oregano, thyme, tarragon, and chives near your back patio or deck for easy access when you’re cooking.

At This Time: Second week of May (or when temps don’t dip below 55 degrees at night)
Plant These: Tomato transplants
And Remember: No need to exile your veggies to a hidden corner of the yard. Planting marigolds—which have a strong odor—around the base of tomato plants helps repel pests like the moth that spawns the tomato-loving hornworm.

At This Time: Third week of May
Plant These: Eggplant, sweet chili peppers
And Remember: “Harvest veggies frequently and when their skins are shiny,” Elliott says. “Don’t wait until they’re [fully] mature. The smaller the produce, the more nutrient-dense it is, and the less it’ll be damaged by insects.”