What to plant this week in Wilmington, DE
Wilmington gardeners in Zone 7b can finally put down their frost blankets as the last average chill arrives on March 28, opening up a busy window for sowing warm-season crops like bush beans and yellow summer squash. With coastal breezes often cooling our sandy soils near the Delaware River, this week focuses on getting those heat-loving transplants into the ground before night temperatures dip toward that 5°F minimum.
The next 7 days
Wilmington, DEGrowing in Wilmington right now
- Our sandy loam here drains quickly, so amend new planting beds with compost to help retain moisture for thirsty squash and melons during dry spells.
- Watch for wind shear off the Delaware River when setting out seedlings; use temporary windbreaks or plant in sheltered spots like north of brick walls.
- Since we have no transplants ready this week, focus your energy on direct seeding beans and zucchini while harvesting early basil and borage before they bolt.
- Mulch heavily around winter squash and pumpkins now to conserve soil heat as we move toward the November 15 first frost date.
Sow this week
4 crops- Bush Bean
- French Marigold
- Yellow Summer Squash
- Zucchini
Transplant this week
Nothing is due to go out this week.
Harvest soon
37 crops- Basil
- Borage
- Bush Bean
- Cantaloupe
- Cleome (Spider Flower)
- Cosmos
- Cowpea (Black-Eyed Pea)
- Cucumber
- Edamame
- Fennel
- Flour Corn
- French Marigold
- Garden Verbena
- Garlic
- Gourd (Ornamental/Bottle)
- Honeydew Melon
- Lima Bean
- Loofah (Luffa)
- Malabar Spinach
- Nasturtium
- Okra
- Pole Bean
- Pumpkin
- Roselle (Cranberry Hibiscus)
- Scarlet Runner Bean
- Shiso (Japanese Basil)
- Summer Savory
- Sunflower
- Sweet Corn
- Sweet Potato
- Thai Basil
- Vinca (Madagascar Periwinkle)
- Watermelon
- Winter Squash
- Yellow Summer Squash
- Zinnia
- Zucchini
Seasonal tips
- Start succession sowing with Pole Beans or Peas every two weeks for a continuous supply of fresh pods.
- Pinch back the tops of Basil to encourage bushier growth before the heat sets in.
- Apply a light layer of compost around harvested crops to replenish soil nutrients.
Pest & disease watch
- Spider mites are becoming active in our sandy soils as temperatures climb, especially on stressed bean plants exposed to afternoon sun.
- Watch for aphid colonies forming on the undersides of newly emerging cosmos and zinnia leaves before they spread to your squash vines.
- Monitor for early slug activity near moist basements and low-lying areas where they target tender seedlings like nasturtiums.
Watering this week
Provide about 1 to 2 inches of water per week, ensuring deep watering during hot afternoons.
Harvest Basil in the morning when essential oils are most concentrated for peak flavor.
Wilmington gardening questions
3Can I start my tomatoes indoors this week in Wilmington?
No, with the last frost still averaging March 28, it is too risky to start heat-sensitive tomatoes or peppers indoors now; wait until mid-April for most hardy varieties.
Is it safe to harvest basil right now before the summer heat kicks in?
Yes, you can pick basil and borage immediately this week, but cut stems back slightly to encourage bushier growth before the July heat sets in.
How should I handle my watermelon and cantaloupe plants near the river?
Keep these heavy feeders well-watered since our coastal sand drains fast, and consider placing a board under developing fruit to keep them off damp soil that promotes rot.
Other cities in zone 7b
12See the full zone 7b guide → · Plan your Wilmington garden in SproutGuide →