Trees, Shrubs, and Groundcovers

• The 'Peace' rose cultivar is the flower-of-choice for special Peace Gardens being built around the world. Introduced in the United States 50 years ago after being smuggled out of France in a brief case, this rose stood as a symbol of hope and has become one of the world's most favorite roses.
• Take stem cuttings of woodies and perennials now. Also collect seed of firepinks, poppy, wild indigo, and bleeding hearts. Fall bloomers that get too tall, such as chrysanthemum, can be cut back by about one half now to reduce their fall height.
• Shrubs and perennials look nice as foundation plantings, but rain may not reach under the eaves, so you may need to water frequently.
• Use pliers to pull up woody seedlings and weeds. Grip the stem at the soil line, twist it around the pliers, and pull straight up. Watering deeply the day before pulling weeds will make the job easier.
• Odd flower formations on rose bushes may be due to cold temperatures during bud formation. Buds so damaged do not open completely, giving rise to a lop-sided flower.
• Miniature roses can be propagated from stem cuttings. Take cuttings with four leaves and insert them into pots filled with moist potting soil. Rooting hormone is optional. Place whole pot in a perforated plastic bag and place in a shady spot. Water as needed. By autumn, cuttings should be rooted.
• A recent study showed that a well-cared-for floribunda rose bush can produce over 250 blooms in its lifetime. Prune off old blossoms from grandifloras and hybrid teas to keep them flowering all summer. On ramblers and small-flowered roses, remove canes right after blooming. Prune rambling and climbing roses immediately after blooming.
• Mimosa trees often disappoint home owners when they die an early death. Lab tests show mimosa deaths, once blamed on wilt disease, result from a combination of wilt and nematodes. New tests will help plant breeders select varieties resistant to both problems.
• Climbing roses don't really climb - they have long canes that require support. You'll need to loosely tie the canes to trellises with broad strips of material. Do not use wire, it can damage the cane.
• Determining whether you have Chinese or Japanese wisteria is not difficult. The blossoms on the Chinese variety open before the leaves appear. On the Japanese type, they develop with the unfolding leaves. Also, Chinese wisteria usually has 7 to 13 leaflets, while the Japanese type has 13 to 19.
• Alkaline soil can cause leaf yellowing (chlorosis) of some shade trees. If you suspect alkaline soil to be the cause of leaf yellowing on one of your trees, determine soil pH. Pin oaks are especially susceptible to this condition. High soil pH limits the availability of micronutrients.
• Watch for and control black spot and powdery mildew on rose foliage.
• Summer plantings of shrubs are possible if you use container- grown plants. Water newly planted shrubs frequently.
• Put up stakes or guards to protect young trees from lawnmower damage.
• Spring-flowering shrubs, such as deutzia, weigela, viburnum and forsythia, should be pruned as soon as they complete bloom.
• Lacebugs feed on azaleas, pyracantha and other woody plants, causing a gray, blanched or stippled appearance on the upper surface of the leaves. Take steps to control them as soon as you notice the damage. Check with your Extension agent for current pesticide recommendations.
• Mid- to late-June is an excellent time to take softwood cuttings of shrubs to start new plants. Some shrubs propagated in this manner are spirea, boxwood and azalea.
• Plants wilt from a lack of oxygen as well as a lack of water. When the soil is compacted, the plant's tender feeder roots and root hairs suffocate. The problem is compounded when the well-meaning gardener assumes that the wilting is a sign of water stress and immediately irrigates. Well-aerated soil, enriched with organic matter, allows both air and water to circulate freely about the root system for a vigorous plant.
• When you buy container-grown nursery stock, check the root ball, and make sure it is not bound too tightly. A mass of circling roots will stay that way even after it is in the ground.
• Take care that newly planted trees and shrubs receive a thorough soaking each week. Soak the ground; do not sprinkle it lightly. Mulch to conserve moisture. It is also helpful to make a shallow depression around plants to collect water.
• Additional pruning may be required this month on fast-growing plants, such as juniper, privet and yew, to maintain a desirable shape during the growing season.
• Mulch promotes faster growth of trees and shrubs than grass or groundcovers. In three experiments across the country, researchers have shown that a number of different trees and shrubs including dogwood, forsythia, Burford holly, Japanese black pine and cottonwood had growth reduced significantly by both groundcovers and grasses growing up to the trunk.
• When it is necessary to transplant woody plants in hot weather, drape them with a wet sheet after they are planted. Dampen the sheet two or three times a day keeping the plant covered for several days. This will help the plants survive the untimely move.
• When dead or damaged branches are found on shade trees, prune them out immediately