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Gardening Tips

Gardening Tips Regions

Divide late-summer or autumn-flowering perennials. If necessary, go after phlox and artemisia with a sharp spade or even an ax. If delphiniums need to be divided, remove and replant the new little plants growing around the outside of the clump. Discard the hard old heart.

Trim climbing roses and attach securely to fences or trellises.

Scatter crushed eggshells in a thick ring around roses to deter slugs.

Melons often benefit from supplemental warming, such as that provided by growing under plastic. Wait until the transplanted seedlings are established, as they cannot take up moisture very well at first and can easily get dehydrated.

Mulch between rows and keep the garden weeded to give emerging seedlings a fair chance.

Get that herb garden started by putting in plants. If you include mint, plant it in a large plastic tub (the kind drywall joint compound or birdseed comes in) with its bottom removed. This will help keep it from invading the rest of the garden.

An established asparagus bed will be ready to harvest. Patrol daily and select spears of about the same size (which will require the same cooking time). If you had trouble locating those first spears, mark the bed with stakes so that you can find them next year.

Watch for signs of drought in plants transplanted from containers. Apply water (not much, but often) close to each plant's stem, where it will percolate down to the root ball. The larger the plant, the longer the recovery period, and the more diligently you need to water. Poke a pointed metal rod into the soil above the root ball. If the rod doesn't penetrate easily, the soil is too dry. If it moves around and feels squishy, the soil is too wet.

Moles generally come calling this month. They're searching for mates and also grubs in your lawn. To get rid of the grubs, apply milky spore disease (Bacillus popilliae or Bacillis lentimorbus), a dust you can buy at your local garden center. Or try a new product called Mole-Med, which has castor oil as its active ingredient. Moles don't like the taste of this any more than you do. See Almanac.com/Gardening for more tips on pest control.

Don't be in a rush to plant tomato, eggplant, pepper, okra, and other heat-loving seedlings if you live where late-May frosts are common.

Don't cut the leaves off spent spring-flowering bulbs. Dying and yellowing foliage may look unsightly, but leave it in place (and don't tie it up) to help the bulbs ripen for next year's show.

Mow your lawn when the grass is dry. To keep a healthy lawn, never cut more than one-third off the total grass height.

Start cucumber, cantaloupe, summer squash, and watermelon seeds indoors.

Sow more cool-season vegetables outside: beets, carrots, lettuce, chard, and radishes.

Sow green beans, sweet corn, pumpkin, and melons.

Start hardening-off tomatoes.

Plant sweet potato slips.

Harvest rhubarb. Pull off leaf stalks instead of cutting them.

Protect beets from leaf miners by placing row covers over them.

Finish pruning spring-flowering shrubs that are done blooming.

Finish cutting back the dead branches on perennial flowers and other shrubs.

Supply your taller plants with supports; the growing plants will hide the supports and be more stabilized.

Remember to water your plants and lawns, especially newly panted seeds.

Apply fertilizer to give the vegetable garden a good start.

Control weeds before they seed!

Begin planting warm-season annuals and summer bulbs, such as dahlias and cannas.

Mulch around your newly-planted flowers, vegetables, shrubs, and trees to help reduce weeds and retain moisture.

You can place houseplants outside once the nights remain above 50 degrees.

Sow cabbage, Brussels sprouts, and cauliflower indoors for fall garden transplants.

Summer flowers can now be planted; plant summer bulbs such as cannas, dahlias, and gladiolus.

Pinch back growth of newly planted annuals and perennials; this will help the plants develop more flowers.

You can prolong the flowering season for your spring annuals by cutting off the old blossoms.

Cool-season vegetables will quickly decrease in quality once the weather gets hot. Be sure to harvest these vegetables and then replace them with warm-season vegetables such as okra and sweet potatoes.

As the weather warms up, increase the frequency of watering. Keep your plants well-watered throughout the growing season.

Apply mulch around heat sensitive plants to keep the roots cool and to prevent water evaporation.

Put shade cloth over tomatoes.

Be aware of insects. Many bugs appear in May, including lace bugs, aphids, and bagworms.

Fertilize both cool-season and warm-season lawns.

Seed Bermuda and warm-season grasses as soon as the soil warms up. Apply 1 inch of water per week.

Once every 2 or 3 years, dethatch Bermuda lawns during their active growing season (May through August).

Continue fertilization of your rose bushes; liquid fertilizers can be added every two weeks.

Take care to keep deciduous fruit trees well-watered this month. Do not prune.

Cover fruit trees with netting to protect the fruit from bird damage.

You may place houseplants outside once the nights remain above 50 degrees.

Thin early seeded root and leaf crops. Keep well watered!

Cover tender plants if late frost is in the forecast.

Sow a second crop of beets, carrots, radishes, leaf lettuce, and chard for continued harvest.

In many areas, it's time to plant beans, sweet corn, potato slips, pumpkin, and watermelon.

Protect beets from leaf miners by placing row covers over them.

Start cucumber, cantaloupe, summer squash, and watermelon seeds indoors.

Before transplanting indoor plants, harden them off. Put in a sheltered spot during the day and bring them in at night. Then gradually increase their exposure to sun, wind, and cool temperatures.

Harvest rhubarb. Pull off leaf stalks instead of cutting them.

Start hardening off tomatoes. Set up stakes or cages when you transplant.

See Almanac.com/Gardening for the Best Dates to Transplant.

Be sure to weed your garden before the weeds go to seed.

Be aware of insects. Many bugs appear in May, including lace bugs, aphids, and bagworms. See Almanac.com/Gardening for tips on pest control.

Plant annuals (flowers).

Spread a little lime or wood ashes around delphiniums and peonies.

To encourage constant flowering, routinely remove spent blossoms and keep them from getting bone-dry.

Prune spring-flowering shrubs as soon as the flowers fade. For forsythias, cut the oldest stems to within a foot of the ground, but be sure to let the plant keep its arching form; don't turn it into a gumdrop or cannonball.

Mulch around your newly planted flowers, vegetables, shrubs, and trees to help reduce weeds and retain moisture.

Stake up and support any tall plants before they start to fall over.

As the weather warms up, increase the frequency of watering. Keep your plants well watered throughout the growing season.

If delphiniums need to be divided, remove and replant the new little plants growing around the outside of the clump. Discard the hard old heart.

Begin planting warm-season annuals and summer bulbs, such as dahlias and cannas.

Pinch back growth of newly planted annuals and perennials; this will help the plants develop more flowers.

Watch young transplants carefully. Water them shallowly but often and close to the stem so that the water will reach roots.

Mulch between the rows of your garden to help deter weeds.

Continue fertilization of your rosebushes; liquid fertilizers can be added every 2 weeks.

Take care to keep deciduous fruit trees well watered this month. Do not prune.

When fruit trees are in full bloom, avoid spraying insecticides that will kill honeybees.

Start looking for tent caterpillar nests in fruit trees and remove. Spray water or B.t. to safely remove without harming trees.

Cover fruit trees with netting to protect the fruit from bird damage.

When adding mulch around trees, do not spread up to the tree trunk, and remove old mulch.

Mow your lawn when the grass is dry. To keep a healthy lawn, never cut more than one-third off the total grass height.

If you're growing plants outdoors in containers, don't use a soilless potting mix. Be sure it contains at least half soil. Or make your own blend for window boxes and patio containers by mixing one part compost, one part garden soil, and one part builder's sand.

Sow cabbage, brussels sprouts, and cauliflower indoors for fall garden transplants.

Fertilize your rhododendrons and azaleas with an acid-based fertilizer if needed.

If soil temperature is above 70 degrees, you can now plant eggplants, melons, tomatoes, squash, and peppers.

Manage weeds while they are small and still growing.

Watch out for pests in the garden. Trap moles and gophers as new mounds appear.

Check your plants for any insects, such as aphids, cabbageworms, black beetles, and root maggots and control as needed. (See our Pest pages for advice.)

When the soil is warm, apply a layer of mulch around your plants as long as there are no weeds. Mulch discourages weeds and helps to conserve moisture.

Continue to mow your lawn regularly. If you use any lawn food, be sure to keep it away from your plants.

Lay soaker hoses or drip lines on garden beds to conserve water.

Plant bedding flowers in moist soil and remember to keep them well watered.

Prune your flower shrubs after they have finished blooming—azaleas, forsythia, lilacs, and rhododendrons. You can also prune evergreens once new growth appears.

Fertilize your roses and check for diseases; treat if needed.

Cut back spring-blooming perennials to about 3 inches in height after they finish blooming. Sow more perennial seeds and set out new perennial plants.

Plant dahlias, gladioli, and tuberous begonias.

You can sow hardy annual seeds now, such as calendula, cosmos, and sweet peas.

Make another planting of warm-weather vegetables such as beans, corn, squash, eggplant, tomato, and peppers. Southern favorites include okra, southern peas, and sweet potatoes.

Make sure that crops have plenty of mulch during dry spells.

Remove suckers from your tomato plants. Be sure that the plants are tied up on stakes or trellises and vines are not on the ground.

Continue to plant heat-loving herbs, including bail, oregano, sage, Mexican tarragon, and rosemary.

Watch out for insects devouring your plants, especially tomatoes. See Almanac.com/Gardening for our Pest pages to control them as early as possible.

Water early in the morning and deeply, avoiding leaves.

Fertilize your annual and perennial flower beds.

Remove any dead flowers from your plants to encourage new growth.

Plant annuals that can take the summer heat, such as angelonia, wax begonia, and ornamental pepper.

Plant bulbs for a summer of color, including early- to late-blooming varieties of daylilies.

Bring your houseplants outdoors to help rejuvenate them. Check them for any diseases or insects.

Newly planted shrubs require special attention. Be sure to keep them well watered and mulch around them if you have not already done so.

Keep your lawn healthy by watering, fertilizing with control-released nitrogen, and mowing regularly to prevent pests.

For healthy grass, avoid weed and feed products. Only apply herbicides to areas with weed infestations.

Watch out for lawn insects and use control measures. See your local lawn care center.

Mow your lawn at recommended heights (St. Augustine and Bahia: 3 to 4 inches; Centipede: 1.5 to 2 inches; Dwarf St. Augustine: 2.5 inches).

Finish pruning spring-flowering trees and shrubs after they bloom. Lightly prune azaleas.

Get ready for hurricane season. Check your trees for damaged or weak branches and prune as needed. Consult a professional.

Mulch between the rows in your garden to help control soil temperature and retain moisture.

Be sure to check your plants for any diseases or insects; treat them when necessary.