June Gardening Checklist

Useful tips and things to check of your June gardening checklist


  • Stake peonies. Later pinch stalks below withered flowers and add light feeding of composted cow manure.
  •  Good air flow and drying conditions around plant foliage will aid in reducing leaf spot diseases.
  •  Keep your gardens weeded. Weeds steal moisture, nutrients, space and light from your plants.
  •  Ornamental grasses can add interesting forms and textures to your garden. They look great blowing in the breeze on a hillside or in the distance around a pond.
  • Plant perennials in clusters of three or more for masses of color.
  •  Set out Japanese Beetle traps.
  • Time to weed & mulch your gardens if you didn’t do it in May.


  • Install your yearly annuals and feed them with miracle grow. Design you pots and don’t be afraid to put herbs in with your annuals. 
  • Flowers drooping on cucumber, cantaloupe and squash are not a problem. These are male flowers, and the first female flowers will be along shortly. Know the female flower by the thick knuckle which shows under the flower. Once pollinated, this becomes the squash you serve on the dinner table.
  •  Thin seedlings in the vegetable planting.
  •  First adult Japanese Beetles begin emerging in late June and are found on bedding plants, shrubs, etc.
  •  Prune Black Raspberry canes to 24” from the soil to increase July harvest.
  •  Standing over cabbage plant, use both hands to grip cabbage head, then lift gently from soil, allowing plant to settle back in soil immediately. This severs surface roots to prevent cabbage head from splitting.
  •  For larger fruit, thin crowded clusters of apples, pears and peaches.
  •  Take snippets of tarragon, basil, oregano and other herbs early in the day.
  •  Store leftover seeds in a sealed container in the refrigerator.
  •  Sow beans every three weeks through midsummer. Pinch back annuals for bushier plants.
  •  Work some straw under ripening strawberies to prevent rotting of berries in contact with damp soils.


  •  When Rhododendron flowers have dropped, finger-prune immediately below the remains of the blossom to permit new growth and formation of new flower buds in late summer.
  •  Prune hedges leaving the bottom wider then the top.
  •  Black Vine Weevils start notching Rhododendron leaves. Use a flashlight to look for weevils at night when they are feeding.
  •  Check trees, shrubs & evergreens for spider mites and scale. If you apply pesticides, do so when bees are not active.
  •  When tropical weather arrives, the spider mite populations explode. Watch for damage from spruce spider mite on arborvitae, hemlock, juniper, pine and spruce, including Alberta Spruce.
  • White deposits on shredded mulch are fungal growths and are not harmful to plants; overturn mulch and growths will stop.
  •  Apply ground limestone to soil around lilacs which failed to bloom this year.


  •   Water lawns and gardens during the morning hours.
  •  The numbers on fertilizer bags (such as 10-10-10) are percentages by weight of nitrogen, phosphorous and potassium.
  •  When mowing the lawn, don’t remove more than one-third of the leaf blade at a time.
  •  Rake up grass clippings after mowing.


  • Move houseplants outdoors on a cloudy day.
  •  Don’t leave any water retaining receptacles (toys, old tires, etc.) around the yard. They make ideal breeding places for mosquitoes.
  • Clean the bluestone patio and add stonedust as needed in seams.
  • Clean off outdoor furniture of spring pollen.