Early May
It’s time to . . .
- Weed now while weeds are small, young, and don't have seed heads.
- Harvest rhubarb stalks larger than 1/2 inch in diameter by twisting and pulling at the base of the stalk.
- Plant transplants of broccoli, brussels sprouts, cabbage, cauliflower, parsley, lettuce, and escarole now.
- Seed or sod new buffalo grass or blue grama lawns within the next few weeks.
- Water established bluegrass lawns deeply, about 1-1/4 inch once a week, if the weather has been dry.
- Mow lawn to maintain a height of 2-1/2 to 3 inches. Cut off only about one-third of the blade height at a time.
- Cut dead flowers from spring-blooming bulbs, but leave the leaves until later because they provide food for next year's bulbs. Pull leaves after they yellow and come out easily. Scratch bone meal or other high phosphate fertilizer around the plants.
- Mark the place where bulbs are growing if you want to move them. They may be moved in the fall.
- Continue planting perennials, and sow annual seeds directly into perennial beds for continued color.
Average last frost date: May 10th to 15th |
Mid-May
It's time to . . .
- Check for insects, especially whitefly, on purchased plants.
- Prune spring-flowering shrubs, if needed, right after they have finished flowering.
- Shape pine by snapping off a portion of new growth "candles". When the time is right, they snap off easily.CSU Fact sheet 7.205
- Plant summer bulbs, such as gladiolus and canna, now. Sprinkle 5-10-5 fertilizer in holes before inserting bulbs.
- Plant basil, cosmos, four o'clock, portulaca, alyssum, cleome, sunflower and other annual seedlings or seeds outdoors.
- Stake taller perennials, like peonies and delphiniums, before they start to flop.
- Plant container roses.
Late May
It's time to . . .
- Harvest asparagus stalks larger than 3/8 inch until about the end of June. Cut just at soil level.
- Transplant tomatoes when the soil is warm. A good tomato transplant will be at least as wide as it is high with a pencil-thick stem and six to eight dark-green leaves. Set plants one inch deeper than in the pot or in a shallow trench with the stem horizontal.
- Plant corn, bean, pumpkin, squash, cucumber, and early-maturing melon seeds now if the soil is warm.
- Plant eggplant and pepper plants only if the soil has reached at least 50 degrees.
- Fertilize lawn now or during the first week in June. Use one pound of actual nitrogen per 1,000 square feet.
- Fertilize roses once they have leafed out. Follow recommended rate instructions exactly.
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