This guide is tailored for the western valleys of Oregon and Washington.
Reader’s suggestions requested. Also please note that if you, the reader, have any suggestions for additions to this month’s list, please put them in the comments section of this article, and I will add them to the list. Thank you! —Nathan
YOU can help to make the world a better, a more friendly, loving and beautiful place by tending your spot on this earth that has been given to you—your garden. Here is a to do list to help you to do just that…
Tree and Shrub Care
- Mulch. Apply two to three inches of mulch around all trees and ornamental shrubs. This helps to fertilize the plants and feed the soil, and also protects them against weed growth and loss of water when the warmer weather returns.
- Pine tree pruning. Don’t do major pruning of pine trees during the growing season, since this attracts sequoia pitch moth infestation.
- Pruning of large trees. Most trees in the temperate western valleys of Oregon and Washington can be pruned anytime of the year. If you’re not sure what to do, or how to do it, call Good News Tree Service, Inc. for a consultation, pruning lessons or to have them do the pruning for you.
- Prune fast growing ornamental shrubs that are beginning to look shabby. You may need to prune them again in the early summer for a more neat and manicured look.
- Reparative pruning. Repair winter damaged to trees and shrubs.
- Tree and shrub removal and stump grinding can be done all year long.
- Trees. Have an ISA Certified Arborist with an ISA Tree Risk Assessment Qualification (like Good News Tree Service, Inc.) inspect your large trees for the potential of failure due to weak root systems and defects in trunks and branches. This can be done anytime of the year.
- Rhododendrons. Remove old blooms (called “dead heading”). Though it looks better aesthetically to remove the dead blooms, it doesn’t hurt the plants to leave them on.
Plant Health Care
Good News Tree Service, Inc. provides full plant health care services as listed below.
- Apple scab on ornamental crabapple and fruiting apple trees. The first visible symptoms occur on leaves in spring as pale, yellowish, water-soaked spots the size of a pinhead. These enlarge, becoming darker and smoky in appearance, later taking on an olive shade and ultimately a brownish black color. Spots may be any shape but are frequently circular. Young infections often show a radiating spread of fungal tissue through the leaf, and such areas later appear as irregular, brown-colored infections. Diseased leaves can be curled and distorted and often drop early. This fungal disease can also move into the fruit to produce a scabby effect, hence the name “apple scab.” Several fungicidal sprays are required to control this disease just prior to flowering and after flowering.
- Arborvitae Twig Blight (Thuja occidentalis): Spray in the spring and early summer when new growth starts at two week intervals.
- Bronze Birch Borer: Begin treating in mid-May through June. This is the only time of year that this beetle can be effectively controlled.
- Cherry Leaf Spot: Spray cherry trees for leaf spot. Apply first spray at petal fall and two weeks later.
- Cherry Tree Brown Rot Blossom Blight (Monilinia fructicola):Make 3 foliar applications starting at bud break and at 14 day intervals.
- Coryneum Blight (Shot Hole Fungus) or Cherry Leaf Spot: This leaf blight affects ornamental and flowering cherry, plum and prune trees. Spray at petal fall, shuck fall and two weeks later.
- Deep Root Fertilization: Trees and ornamental shrubs—deep root fertilize to promote lush, healthy-looking and vigorous crown growth. Urban soils tend to lacking in many of the nutrients that trees and shrubs need to survive. Many are malnourished or are starving to death, which is why they don’t look radiantly healthy are struggling with pest issues. Deep root fertilization helps to promote healthy-looking and pest-resistant trees and shrubs. The best time of the year to do this is in the spring and fall.
- Dogwood Anthracnose: Spraying with a fungicide at bud break and continue at 10 to 14 day intervals.
- Lawns: Fertilize lawns.
- Leaf Blights: Spray trees and shrubs for fungal leaf diseases (e.g. powdery mildew, leaf blights, dogwood anthracnose, needle blights, etc.).
- Monitor trees and shrubs for insect pests. Piercing and sucking plant pests (e.g. aphids, lacebugs, scales, weevils, mites, etc.) are now out and active. If major infestation occurs, plan a course of action to treat your trees and shrubs against these pests. Small numbers of piercing and sucking insects are not harmful to plants. In fact, they provide food for the beneficial, predatory insects that feed on them. To control harmful insects, one can apply systemic insecticides against piercing sucking insects (aphids, lacebugs, scales, weevils, etc.) via soil injections (one treatment gives season-long control). If applied according to label directions, this will kill only the harmful and not beneficial insects.
- Photinia Leaf Spot: Spray with a fungicide as new shoots are developing at 30 day intervals.
- Pine Dothistroma Needle Blight: Apply fungicide at just before bud break and a few weeks later according.
- Powdery Mildew: Apply a fungicides as soon as symptoms appear. Best efficacy occurs if used before symptoms appear. Use fungicide at 7 to 14 day intervals, or more often if conditions warrant it. If a plant is known to have had powdery mildew previously, apply as buds start to open.
- Spider mites will start to become active as the weather warms. Systemic insecticides are available against this pest.
- Tent Caterpillar: Apply systemic pesticide for season-long control.
- Verticillium Wilt: Soil drench in the spring. Maples are especially susceptible to this fungal root disease as are cherries and plums.
- Willow Twig Blight (scab): Apply two or three applications beginning when new leaves first appear at 10 to 14 day intervals.
Elsewhere in the Garden
- Put slug bait around your flowers and tender perennials like hostas.
- Apply two to three inches of mulch (e.g. bark dust, garden compost or wood chips) on all of your shrub beds. Covering bare dirt areas in your yard with mulch helps to prevent soil compaction from rains, and weed growth, and helps to enrich our heavy clay soils.
- Continue planting annual and perennial flowers.
- Cut English ivy off of the base of trees. (This can be done any time of the year.)
- Feed the birds. Dutifully maintain your bird feeders. Bring life and excitement to your backyard by turning it into a bird sanctuary. The birds will thank you for your generosity by providing you with hours of entertainment, and by eating insect pests that harm your ornamental trees and shrubs. Birds in the yard are not only fun to watch, but they perform the vital task of eating harmful insects.
- Start planting your vegetable garden. Once the soil has dried out, you can begin working it for planting our veggies.
- This is a good time of the year to plant trees and shrubs. Visit your local nursery and select your favorite ornamental shrubs and shade trees. After planting your new shrubs, just make sure that you water them well immediately and regularly subsequently for the first two or three summers until their roots get established. During warm weather (in the 60s to low 80s), deep root water once per week. During hot weather (mid-80s and higher) deep root water at least twice per week.
- Water and fertilize annuals and perennial flowers. The hotter the weather, the more water they will need. Flowers in pots and hanging baskets dry out especially quickly, and so need watering every day or two.
- Fertilize your ornamental shrubs with a slow release fertilizer. If the shrubs have a layer of barkdust or other mulch around them, rake the mulch away and apply the fertilize to the bare dirt, so that it actually reaches the plant’s root zone.