What to plant this week in Wilmington, DE
Wilmington gardeners are in a brief pause between seasons, with the ground still holding winter chill and the average last frost not arriving until March 28. This week marks the final window to plant garlic before the soil freezes too deeply for reliable root establishment.
The next 7 days
Wilmington, DEGrowing in Wilmington right now
- Brackish water intrusion in coastal plots can cause salt stress on newly planted crops; leach soil with fresh water if heavy rain is forecasted this week.
- The Piedmont terrain north of the harbor features clay-heavy soils that drain slowly, so avoid tilling wet patches to prevent compaction before spring thaw.
- Protect young garlic from late-season temperature swings using row covers only after the initial freeze risk has passed in early April.
- Monitor drainage on low-lying areas near the Christina River where standing water can linger longer than in upland neighborhoods.
Sow this week
1 crops- Garlic
Transplant this week
Nothing is due to go out this week.
Harvest soon
2 crops- Daikon Radish
- Garlic
Seasonal tips
- Finish harvesting cool-season crops like Daikon radish before temperatures drop too low.
- Plant cover crops or winter rye now to protect soil structure during the dormant season.
- Apply a thick layer of mulch around garlic plants to insulate bulbs from freezing ground.
Pest & disease watch
- Winter moths may still be active in sheltered spots, leaving egg masses ready to hatch as temperatures rise above 40°F next week.
- Overwintering slugs hide under debris and will target emerging garlic shoots once the ground warms slightly.
- Watch for black rot on daikon radish leaves if humidity remains high during this transitional period.
Watering this week
Water garlic lightly and only when the soil is dry, avoiding wetting the bulbs directly to prevent rot.
Store your freshly harvested Daikon radishes in a cool, humid place like a crisper drawer or sand-filled bin.
Wilmington gardening questions
3Can I transplant seedlings now in Wilmington?
No, with an average last frost date of March 28 and current temperatures hovering near the 5°F minimum, all tender transplants should wait until mid-April.
Should I cover my garlic plants with mulch right now?
Yes, winter varieties often pause growth during cold snaps but will resume quickly once daytime highs consistently exceed 45°F.
Should I cover my garlic plants with mulch right now?
Avoid heavy mulching until after the last frost date to prevent trapping moisture and encouraging rot, but consider a light straw layer once temperatures stabilize.
Other cities in zone 7b
12See the full zone 7b guide → · Plan your Wilmington garden in SproutGuide →