What to plant this week in St. Louis, MO
St. Louis gardeners are in the final sprint before summer's heat sets in, with the last frost officially behind us on average April 3rd and nights cooling down toward that historic 0°F low. This week is your critical window to pull out all those warm-weather giants like cucumbers, beans, and melons from your cold frames or start them indoors for a strong June transplant.
The next 7 days
St. Louis, MOGrowing in St. Louis right now
- Watch for the heavy afternoon thunderstorms typical of our river valley; always mulch heavily around squash and pumpkins to prevent soil splashing that causes fungal rot during these wet spells.
- Our clay-heavy soils in neighborhoods like Creve Coeur or Clayton hold moisture well but can get waterlogged; ensure raised beds have excellent drainage before setting out heavy feeders like okra and sweet corn.
- Take advantage of the mild days ahead to harden off transplants for tomatoes and peppers, as a sudden freeze after our average first frost date of Nov 6th could still catch late bloomers if you delay too long.
Sow this week
No direct sowing windows open this week.
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
- Succession sow bush beans or carrots every two weeks to extend your summer harvest window.
- Pinch back the tips of basil and Italian herbs like summer savory to encourage bushier growth before frost.
- Start planning your fall crop rotation; avoid planting nightshades in beds that held them last year.
- Apply a light layer of compost around perennials now to strengthen roots for winter dormancy.
Pest & disease watch
- Spider mites are beginning to wake up on the undersides of basil and zinnia leaves as temperatures climb above 75°F in urban heat islands.
- Aphid colonies are exploding on new growth of pole beans and sunflowers, requiring early intervention with strong water sprays or insecticidal soap before they bloom.
- Watch for squash bugs hiding under broadleaf weeds near your bottle gourd and zucchini plants; hand-picking them in the morning is most effective here.
Watering this week
Water deeply in the morning to keep roots hydrated during heat waves while reducing fungal risks on leafy greens.
Harvest watermelons when they make a hollow sound upon tapping, ensuring you get the sweetest fruit before the first frost hits.
St. Louis gardening questions
3Can I still start seeds directly outside in St. Louis this week?
No, our soil is still too cool and potentially wet from winter rains for cold sowing; keep warm-season crops like basil and beans indoors until mid-May.
Which crops will be ready to harvest soon if I planted them weeks ago?
Look closely at your basil, borage, and French marigolds for flowers or foliage cuts, plus any early bush beans and zinnias that sprouted in mid-March.
How do I protect my garlic from our freezing winters?
If you planted hardneck varieties like 'Music' or 'Red Leaf,' ensure they are covered with 4-6 inches of straw mulch once air temperatures drop.
Other cities in zone 7a
12See the full zone 7a guide → · Plan your St. Louis garden in SproutGuide →