Timely Tips

What to Do in June 2026
Weekly Gardening Timely Tips from
Cornell Cooperative Extension of Westchester County

June 7 - 13

Perennials: Finish planting new perennials soon so they can begin to become established before the hottest days of summer. New perennials may benefit from regular watering depending on rainfall. Apply an inch of water per week including rain.

Flowers: Seeds of fast-growing annuals can still be sown, such as cosmos, marigolds, nasturtiums, phlox and zinnias directly in the garden. Calla lilies, caladium, canna, dahlia and other tender ornamentals can also be planted now.

Fruits and Vegetables: Plant pumpkins now so they’re ready for Halloween. Fruit trees may naturally shed some immature fruit during the “June drop.” Thinning remaining fruit can enhance quality, size and color, and prevent the tree from bearing every other year due to the stress of supporting too many fruits in a given season. To do this, remove injured and insect infested fruit first, then take off all but the largest fruit per cluster. Spacing for apples should be 4 to 6 inches, peaches 4 to 8 inches, and plums 4 inches apart. Cherries do not need to be thinned.

Trees and Shrubs: Prune spring-flowering trees and shrubs right after their flowers fade, and before next year’s flower buds are set. To slow the growth of true pines, pinch back the “candles” before the needles have fully opened. Slow or shape spruces by pruning lightly after a flush of new growth. Beyond a light shaping, wait until early spring to make significant pruning cuts. Hire an arborist to work on large trees.

Lawns: Avoid fertilizer applications in hot weather, especially if the soil is dry. Fertilizers are often best done at Memorial Day and Labor Day; however, fertilizers should only be applied with advice from a soil test. Contact your local Cooperative Extension for advice.

Houseplants: If you plan to bring houseplants outdoors for a summer vacation, you can do this now. Many houseplants typically like bright light indoors but appreciate shaded conditions outside. To prevent scorching, make sure the plants are acclimated to outdoor conditions and shaded from strong afternoon sun.

Last updated June 6, 2026