Timely Tips

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

April 26 to May 2

Perennials: Lavender has become increasingly popular with the advent of hardier varieties, though it still may be relatively short lived in the Hudson Valley. These plants require full sun and well-drained soil, and even with optimal conditions, they may eventually become straggly. To promote fullness, lavender may be cut back to approximately 6 inches above the lowest new growth. If the plants don’t recover well or continue to look thin, consider replacing older plants with new, or choosing a different species that is better adapted to the site.

Flowers: Continue to sow seeds of hardy annuals (alyssum, dusty miller, marigold, etc.) outdoors. Plant seedlings of these hardy annuals now.

Fruits and Vegetables: Continue to plant and transplant cool-season vegetables, again waiting to plant cauliflower and broccoli until nighttime temperatures are consistently at or above 50°F. Container vegetables can be convenient and practical, arranged in a pleasing way, and grown on a deck or patio with at least six hours of sun. Choose compact varieties. Make sure to use a potting mix (not topsoil) in a good size pot, preferably with a water reservoir.

Trees and Shrubs: Prune early flowering shrubs that have finished blooming, as well as late-flowering shrubs such as butterfly bush, hydrangea and Rose of Sharon. Remove a few of the oldest stems to encourage new growth and those that are very small or thin. Take no more than ¼ to ⅓ of the total growth in a given season.

Lawns: At this time of year, the grass may be growing fast. The more it is mowed, the faster it may grow. To regulate grass growth and slow it down, consider mowing every two weeks. Leave clippings on the lawn unless they form clumps. If necessary pick up clumps, add them to a compost pile, mixing in carbon sources (shredded paper or leaves) as you go.

Houseplants: Continue to shape plants that have grown leggy.

General: Having issues with animals in your garden? Learn more in the Cornell Cooperative Extension of Westchester 2026 Home Garden Lecture Series: Structural Defensive Gardening.

Wednesday, May. 13 from 10 to 11 am, remote on Zoom, $5. All lectures are remote on Zoom. A ticket to any single remote lecture is $5 and the tour is $20 (while there is space).

Speaker: Louis Petralia is a Westchester CCE Master Gardener Volunteer, as well as an attorney, teach ad lawn enthusiast. As a CCE Master Gardener Volunteer, he spends his time working the Demonstration Garden at Hart’s Brook Park and Preserve in Hartsdale, NY.

Check out the brochure at https://www.canva.com/design/DAG37gykNic/RGq-kIdH95APY6-bKoGQYw/view?utm_content=DAG37gykNic&utm_campaign=designshare&utm_medium=link2&utm_source=uniquelinks&utlId=hcc45ab7c29 For more information, please call CCE at 914-285-4640, 914-285-4620 or email westchester@cornell.edu

Last updated April 25, 2026