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Johnson County

Research-based Information You Can Trust — Localized for your needs

Johnson County
11811 S. Sunset Drive
Suite 1500
Olathe, KS 66061

(913) 715-7000
(913) 715-7005 fax
jo@listserv.ksu.edu

Map to our office

May Garden Calendar

Vegetables and Fruits

  • Plant tomato, pepper, and eggplant transplants in early May
  • Seed sweet corn, cucumbers, squash, beans, and other warm season vegetables
  • Lightly cultivate soil with a hoe to control weed growth
  • Mound soil around potato plants to encourage tuber formation
  • Harvest fresh asparagus until the spear size decreases
  • Remove rhubarb seed stalks to encourage leaf growth
  • Plant kitchen herbs for summer use in dishes or food preservation
  • Treat fruit trees with needed pesticides to control insects and disease
  • Thin heavy fruit set on apples to increase fruit size and next year's crop

Flowers

  • Plant annual flowers for summer color
  • Continue to plant and divide perennials
  • Mulch perennial and annual gardens for weed control and moisture retention
  • Begin pinching chrysanthemums for bushier plants
  • Do not remove foliage from spring bulbs until it dies down naturally, this develops stronger blooms for next year
  • Plant container gardens and hanging baskets using a good quality potting mix
  • Keep a garden journal for permanent reference

Lawns

  • Reduce thatch layers from zoysia by verticutting or core aerating
  • Sod or sprig zoysia lawns to fill in bare areas
  • Fertilize zoysia lawns with high nitrogen to promote green up and summer growth
  • Mow zoysia at 1 to 2 inches tall
  • Apply slow release nitrogen fertilizer to bluegrass and tall fescue to promote summer growth if watering during the summer. Lower maintenance lawns skip this application
  • Mow bluegrass and tall fescue at 3 inches
  • Spot treat broadleaf weeds
  • Withhold early summer watering until needed to promote more drought tolerant lawns

Trees and Shrubs

  • Plant new trees and shrubs
  • Prune spring flowering shrubs after bloom to shape plant and encourage flowers next year
  • Mulch around young trees and shrubs to conserve moisture and control weed growth
  • Water young ornamentals as needed
  • Remove tree wraps for summer growth
  • Remove tree stakes that have been in place more than one growing season
  • Fertilize trees to help increase growth rates
  • Caution, use line trimmers around trees and shrubs so as not to damage tender bark

Houseplants

  • Move plants outdoors for summer by gradually increasing the exposure to sunlight
  • Fertilize plants to promote summer development
  • Rotate plants to develop a well-rounded plant
  • Wash dusty leaves in the shower under room temperature water
  • Four to six inch cuttings are a great way to start new plants, root in potting mix under low light
  • Repot plants into a one inch larger pot
  • Check for insects

Return to Garden Calendar

K-State Research and Extension Johnson County Master Gardener logo

Have questions? The Garden Hotline is staffed by trained EMG volunteers and Extension staff who will assist you with questions.

Phone: (913) 715-7050

Email: garden.help@jocogov.org