05 May guide

Warm-Season Gardens Take Shape

Once the last frost passes, May opens the floodgates. Every tender crop, tropical plant, and summer annual can finally go in the ground.

What May means

May is the month most gardeners wait for all year. After the last frost date passes, tender crops like tomatoes, peppers, basil, and squash can be transplanted safely. Summer annuals — zinnias, marigolds, cosmos — fill beds with color within weeks. Mulching is critical now: a 2–3 inch layer of shredded bark or straw suppresses weeds, retains moisture, and moderates soil temperature as summer heat builds. Perennial gardens explode with growth, and quick-spreading plants may need early thinning to prevent overcrowding. This is also the best month to plant container gardens for patios and balconies, since warm nights finally allow tropical and subtropical plants to thrive outdoors.

May tasks

08
  • 01 Transplant tomatoes, peppers, eggplants, and basil into the garden after last frost has passed
  • 02 Plant summer annuals (zinnias, marigolds, cosmos, petunias) in beds and containers
  • 03 Mulch all garden beds with 2–3 inches of organic material to suppress weeds and retain moisture
  • 04 Set up tomato cages or stakes at planting time — adding them later disturbs roots
  • 05 Direct-sow warm-season crops like beans, corn, melons, and sunflowers
  • 06 Thin seedlings of earlier-sown cool crops (carrots, beets) to proper spacing
  • 07 Begin a regular watering schedule — most gardens need 1 inch per week from rain and irrigation combined
  • 08 Scout for aphids and cabbage worms on brassicas; treat early with insecticidal soap or row covers

Plants to start in May

08
  • Tomatoes (transplant outdoors)
  • Peppers (transplant outdoors)
  • Basil (transplant or direct sow)
  • Zinnias (direct sow or transplant)
  • Marigolds (transplant)
  • Beans (direct sow)
  • Corn (direct sow)
  • Melons (transplant or direct sow)

Design tips for May

04
  • 01 Fill gaps in perennial borders with annual flowers for instant color while permanent plants mature
  • 02 Create a "thriller, filler, spiller" arrangement in each container — a tall centerpiece, mounding middle plants, and trailing edges
  • 03 Plant in drifts of 3–5 rather than single specimens for a more cohesive, professional look
  • 04 Install a drip irrigation timer now so watering is consistent through the summer without daily effort
See it first

Render this month's plan on your real yard

Upload a photo and Arden previews how the may additions land before you dig.

Try the AI designer
FAQ

Frequently Asked Questions

01 What should I plant in May?

May is prime time for tomatoes, peppers, eggplants, basil, squash, beans, corn, and melons. Plant summer annuals (zinnias, marigolds, cosmos) for color. Container gardens can be planted with tropical and subtropical plants. It is also the last window for planting perennials before summer heat.

02 Is it too late to start a garden in May?

Not at all — May is actually the ideal starting point for warm-season gardens. You can direct-sow beans, squash, and cucumbers, and buy transplants of tomatoes and peppers from nurseries. Many gardeners have their most successful seasons starting entirely in May.

03 How do I prevent weeds in May?

Apply 2–3 inches of mulch immediately after planting. Weed early and often while seedlings are small — a weekly 15-minute pass prevents hours of work later. In vegetable gardens, consider landscape fabric between rows topped with straw.

Free on iOS and Android

Ready to reimagine your outdoor space?

Download Arden free — see your garden transformed in seconds.

No credit card. No signup. Just results.

Trusted by 200K+ gardeners
8,247 active this week
4.8
★★★★★
App Store
8.2K
Reviews
All time