Monthly Garden Tips: May

Flower/Landscape Gardens

  • The last frost date in our area is May 15; annuals may be planted after this date.
  • Say goodbye to Pansies which were planted last fall. Although they can brave the winter blasts, they will not thrive in our hot and humid summers. Pull them up and replace them with summer loving annuals.
  • Pull weeds like Harry Bittercress and Dandelions now, while they are small and the weather is pleasant, and before they go to seed and multiply.
  • Remove spent flowers from spring bulbs, leaving the foliage to die-back. Fertilize with bone meal scratched into the soil surface at the base of the bulbs.
  • Take pictures of blooming bulbs. This will make it easier to remember where they are located and to color coordinate spring plantings.
  • Dig and divide early blooming bulbs, such as Daffodils, if they are crowded and didn’t bloom well.
  • Plant summer flowering bulbs like Cannas, Gladiolas, Caladiums, and Lilies.
  • Helleborus seedlings can be found growing beneath mature plants. Transplant these to a shady spot to allow them to mature.
  • If necessary, prune early- flowering shrubs, vines and trees after blooming.
  • Stake plants such as Peonies and Dahlias early to enhance your flower borders and make maintenance easier as the season progresses.
  • Begin training and tying vigorous spring growth of vines and climbing roses.
  • Feed roses every two weeks to promote vigorously blooming plants.
  • Lay sod for new lawns.
  • Plant summer container gardens using new soiless potting mix and slow-release fertilizer.
  • Move houseplants outdoors in May. Most houseplants will be quite happy outdoors in full shade. All plants that have been spending the winter inside should start out in full shade and gradually be moved into sunnier areas. The leaves may scorch if exposed to unexpected levels of sunlight.
  • Promptly control insects and diseases using Integrated Pest Management techniques to prevent severe infestations.
  • Deadhead roses regularly to keep them blooming all summer. To prevent cane boring insects from entering the cut rose branch, apply waterproof wood glue to the cut.
  • Watch roses for appearance of black spot. Remove infected leaves regularly (do not add infected rose leaf debris to compost).
  • Be on the lookout for aphids which appear this month. They especially love tender new growth on Roses. If you see aphids hose them off with water instead of toxic chemicals.
  • Apply deer repellents regularly, especially on emerging and existing bulbs, roses, yews, coral bells and other susceptible plants.

Vegetable Gardens and Fruit Trees

  • Thin or transplant seedlings when needed.
  • Sow beans, tomatoes, squashes, zucchini, peppers and melons

 

Call DESIGNS FOR GREENER GARDENS at 410-626-6122 to help you with your May garden needs!