Do you know what vegetable you get if an elephant happens to walk through your garden? Squash.

June is a busy month, not only in the vegetable garden, but in flowers, lawns and landscapes. Following is a June to-do list.

  • Iris are among the most colorful, easy-to-grow perennials that bloom in June. Although August is the preferred time to dig, divide and replant existing iris, potted types from garden centers can be planted throughout the growing season.
  • Increase apple fruit size and quality by thinning overcrowded apples when dime-sized, spacing them four-to-six-inches apart. Remaining apples will be larger and higher quality.
  • When watering lawn, garden and flowers, do so in early morning, if possible. Foliage will dry more quickly, reducing chance of disease.
  • Fertilize trees, shrubs, perennial flowers and fruits with granular or water-soluble types in early June. Repeat in late June, if desired. Fertilizing after July 4 can cause late-season tender growth that is more prone to winter injury.
  • Fertilize geraniums and other annual flowers in hanging baskets and containers regularly throughout the season. A steady flow of nutrients encourages continued bloom.
  • Coax annual flowers to continue season-long bloom by removing flowers as they fade and before seed pods form, which is especially important on geranium, marigold, zinnia, salvia, cosmos, and any types that form a large seed pod or stalk.
  • Remove spent, withered blossoms from peony, iris and other perennials to prevent seedhead formation.
  • Remove sucker shoots and trunk sprouts from the base of lindens, basswood, poplars, Japanese tree lilac, Canada red cherry and fruit trees.

When apples are dime-sized, remove excess so the remaining fruit is four to six inches apart. David Samson / The Forum
When apples are dime-sized, remove excess so the remaining fruit is four to six inches apart. David Samson / The Forum

  • Apply insecticide to the base of squash vines by late June to kill squash vine borers before they enter stems, causing wilting and death. Thoroughly treat stems from ground level outward at least 12 inches with Sevin, spinosad or permethrin.
  • Monitor tomato plants for leaf spots and blights. Garden disease preventative fungicides are best applied while foliage is healthy. Avoid wetting foliage when irrigating to avoid splashing disease organisms from soil onto leaves.
  • Tomato blossom end rot, which causes sunken, brown or black lesions on fruit bottoms, can be reduced by keeping soil moisture uniform and by avoiding root damage from too-close hoeing. Mulch plants in late June with straw or herbicide-free grass clippings.
  • Hill potatoes by hoeing up soil around the plant’s base to prevent sunlight from turning exposed tubers green.
  • By the end of June, plant a second crop of lettuce, beets, spinach and radishes to enjoy later in the season.
  • Water lawns deeply and less often, which creates a deeply rooted, healthy turf. Apply one inch of water per week in one application, or divided in two if soil is light and sandy. To monitor how much water your sprinkler is applying, set a straight-sided soup or tuna can on the lawn.
  • Frequent, shallow sprinklings create shallow roots, causing the turf to be more susceptible to heat stress and invasion by weeds and pests.
  • Raise the lawnmower’s mowing height to three inches. This generous mowing height will keep the lawn looking neat and lush green, as the roots remain cool, moisture is conserved, and weeds are lessened.
  • Sharpen the lawnmower blade. A dull blade shreds the grass blade tips, giving the entire lawn a gray appearance.
  • Spot-spray weeds in early June. Always follow label directions carefully to prevent collateral damage to landscapes, trees, flowers and vegetable gardens.
  • If lawns have been sprayed with herbicide, don’t use the clippings for mulch, or haul to waste collection sites until the third mowing, as previous clippings are tainted.
  • If dry weather continues, lawns have the ability to go dormant, turn brown, and “hibernate” until moisture improves. However, grass plants do need some moisture to prevent death or thinning of the lawn. About once a month apply at least a quarter-inch of water during periods without rain, to keep the grass plants alive.
  • Begin spraying about June 20 to control apple maggots with Sevin or spinosad insecticides at seven-to-ten-day intervals through August. Apple maggots are responsible for the brown streaks inside apples
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Don Kinzler, a lifelong gardener, is the horticulturist with North Dakota State University Extension for Cass County. Readers can reach him at donald.kinzler@ndsu.edu.