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May Gardening Tips

Gardening Information

Prune spring-flowering shrubs such as forsythia, lilac, and quince, as soon as the bloom is finished. Remove older stems, broken, dead, or crossing branches.

Watch for aphids on new growth of roses, perennials, and spiraea. Spray them with a strong stream of water or use an insecticidal soap to control the insects.

Plant trees, shrubs, and perennials obtained from the nursery now. The cool weather and spring rain we usually receive is optimal for new plants.

It is not too late to apply a pre-immergent herbicide to control crabgrass and other annual weeds. Be careful not to use the chemical on vegetable garden or flower beds that will be seeded later as the weather warms.

Cut the spent flowerheads of spring flowering bulbs such as daffodils and tulips. Do not cut back the leaves of these plants until the foliage begins to fade and turn brown since the bulbs need the food produced by the leaves to feed the bulb for next year's bloom.

After the first grass mowing of the season, raise mower blades to their proper cutting height. For Kentucky bluegrass and other cool season turf grasses, that is from 2" to 3" inches high. Keeping the turf grass at this height will promote root growth, conserve water, reduce weeds, and provide for a healthier lawn.

Mulch bare ground to conserve moisture and control weeds.

It is not too late to aerate lawns to improve supply of air, water, and nutrients to turf root systems. Power raking should only be done where extreme amounts of thatch have built up in the turf.

As soon as garden beds are dry enough to allow working the soil, apply and dig in compost or peat moss to increase water-holding ability.

Begin setting out hardier potted plants such as geraniums on decks, porches, and patios. Wait until danger of frost is past to pot-up other tender, less hardy plants. Want to learn about native plants for water conservation, perennial and herb care, or how to use stone in the landscape? Check out our May CALENDAR for useful classes!