What to plant this week in Madison, WI
In Madison, the calendar officially flips on May 1st as your average last frost date arrives, signaling that you can finally move those hardy transplants out of your garage. With nighttime temperatures hovering just above freezing and soil still holding winter chill in shaded areas, patience is key before pushing seeds into the damp earth.
The next 7 days
Madison, WIGrowing in Madison right now
- Madison's clay-heavy soils stay cold longer than other zone 5b cities; wait until the top inch warms to at least 40°F before sowing early crops like peas or radishes. If you have heavy clay in your backyard, mix in compost now to improve drainage for the upcoming wet spring showers typical of the region.
- Be prepared for 'false springs' where warm days trick plants into budding only to be killed by a sudden late frost; cover sensitive starts with row covers if temps dip below 28°F overnight. The area's high humidity also demands extra vigilance against fungal issues on crops like brassicas and leafy greens.
- Take advantage of the mild May weather to sow warm-weather giants immediately; varieties listed for immediate harvest like bush beans, cucumbers, and zucchini thrive once soil penetrates past the frost line.
Sow this week
No direct sowing windows open this week.
Transplant this week
Nothing is due to go out this week.
Harvest soon
44 crops- Basil
- Borage
- Brussels Sprouts
- Bush Bean
- Cantaloupe
- Celery
- Cleome (Spider Flower)
- Cosmos
- Cowpea (Black-Eyed Pea)
- Cucumber
- Dahlia
- Edamame
- Fennel
- Flour Corn
- French Marigold
- Garden Verbena
- Garlic
- Ghost Pepper (Bhut Jolokia)
- Gourd (Ornamental/Bottle)
- Habanero Pepper
- Honeydew Melon
- Leek
- Lima Bean
- Lisianthus (Prairie Gentian)
- Loofah (Luffa)
- Nasturtium
- Ornamental Sweet Potato Vine
- Parsnip
- Pole Bean
- Potato
- Pumpkin
- Roselle (Cranberry Hibiscus)
- Scarlet Runner Bean
- Shiso (Japanese Basil)
- Summer Savory
- Sunflower
- Sweet Corn
- Thai Basil
- Vinca (Madagascar Periwinkle)
- Watermelon
- Winter Squash
- Yellow Summer Squash
- Zinnia
- Zucchini
Seasonal tips
- Harvest bush beans, cucumbers, and yellow summer squash regularly to encourage continued production.
- Deadhead spent flowers like cosmos and zinnia to keep the plants looking tidy and blooming longer.
- Check on garlic scapes if planted early this spring; it's time to harvest them soon.
Pest & disease watch
- Watch for early aphid colonies forming on the undersides of seedling leaves as the humidity rises in late April and early May.
- Slugs are active now in Madison's shaded garden corners; set out beer traps or hand-pick them in the evening before they damage emerging transplants.
- Powdery mildew can strike quickly on susceptible varieties like squash and melons if foliage stays wet from spring rain; ensure good air circulation around plants.
Watering this week
Water deeply in the morning to keep roots hydrated during this warm growing season while letting soil dry slightly between sessions.
Pinch back any leggy basil or shiso plants now to promote bushier growth before the heat peaks.
Madison gardening questions
3Can I plant my tomato starts right now?
Yes, May 1st is your average last frost date in Madison, making it safe to move hardy transplants outdoors provided there are no freezing temps overnight. Check that the soil has warmed slightly before planting to ensure strong root establishment.
What vegetables can I harvest this week?
If you planted winter squash or garlic earlier, you may see early signs of growth, though most summer crops listed for harvest soon like bush beans and zucchini need warmer soil first. Focus on checking overwintered garlic for green shoots rather than expecting a full harvest yet.
How do I handle the clay soil in my Madison garden?
Madison's native clay retains moisture well but dries out slowly, which can stunt root growth if not amended with organic matter. Incorporate plenty of compost or aged manure into your beds now to lighten the texture for better drainage before heavy rains hit.
Other cities in zone 5b
8See the full zone 5b guide → · Plan your Madison garden in SproutGuide →