Plant flowers (© none)

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Gardeners, it's time to test your mettle. If temperatures are cooperating, the merry, merry month of May may be your busiest until September, with planning, planting and patio projects to lead the way into summer.

Don't be fooled by a late frost: Find out the mean freeze date in your area, and be sure soil is warm and workable — not too wet, not too dry — before putting tender plants in the ground.

Get those showy summer sprays of color started by planting bulbs of dahlia, lily, tuberous begonia and gladiolus.

Plant a few "gladdie" corms every week from now until early July for continuous summer cuttings.

  • As their blooms fade, remove the flowers from tulips and daffodils and give them a dose of fertilizer. But leave those leaves where they are: They're needed to produce next year's buds. Peonies, too, will be hungry for fertilizer now.
  • Got mums? From now until the beginning of July, you can make chrysanthemums bushier and more productive if you pinch a half-inch off of each stem when they're 6 or 7 inches high.

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Early in the month, get a jump on flower planting with hardy annuals such as dianthus, petunias, snapdragons and pansies.

  • If another frost threatens to sneak up on you, cover annuals overnight with thin burlap or newspaper.
  • Most summer-flowering annuals can also be put in the ground now.
  • Hang mixed baskets of fuchsias, geraniums and impatiens when the evenings warm up, and plant zinnias, lobelias and marigolds in the ground or in containers.
  • When you're safely in the no-frost zone — probably midmonth or a bit later — you can set out those six-packs of seedlings to harden them off before transplanting.

As the shoots of your old friends start peeking up through the soil, give them a light dose of fertilizer. Then head for the nursery to start selecting this season's new perennials, many of which can be planted now if you're sure Jack Frost has left town.

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  • There's still time to plant the early birds such as primroses, coral bells, candytuft and saxifrage.
  • In mild climates, start adding summer-flowering plants such as phlox, daylilies and delphiniums.

Lawn care
If you haven't done so already, assess the needs of your lawn now.

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  • Toss the moss, thatch and weeds.
  • Aerate, feed and overseed to get rid of bald patches.
  • Around midmonth, feed grassy areas with an even coat of high-nitrogen fertilizer.
  • Unless spring showers are on their way, follow up with a good thirst-quenching dose of water.
  • Anxious mowers, get out your measuring tape: When grass reaches 3 1/2 to 4 inches, bring out your tuned-up machine and let 'er rip, leaving grass 2 1/2 to 3 1/2 inches high. A bit of extra height is good for its health, leaves shorter clippings (leave them in place to nourish the lawn) and cuts down on weed growth.

As you're planting your vegetable garden, consider planting times as well as plant compatibility.

  • In most climates it's safe now to seed or plant hardier vegetables such as beans, peas, potatoes, lettuce, carrots, corn and chard.
  • When you're sure the soil is thoroughly thawed and warm (at least 60 degrees), go ahead and sow cucumbers, squash, melons, peppers, tomatoes and other tender annuals.
  • Plant celery and cucumbers near your bean starts — they make good neighbors!
  • Beans also get along well with peas, corn and potatoes, but keep them away from "aromatic" vegetables such as leeks, garlic, onions and shallots.
  • Carrots, tomatoes and lettuces also like each other's company — just be sure not to mix them with dill.
  • Seeds of corn, pumpkins, squash, beans and melons can be sown directly into the ground now.
  • If you sow vine crops for later transplant, use peat pots. At planting time, bury the whole pot so fragile roots don't become damaged.