June: Enjoying summer's opening days
by Mary Robson, WSU Area Extension Agent
Light, long light evenings--it's June. Gardeners can move outside early in the morning or late in the evening, experiencing glorious long days for garden work and play. Explore parks, botanical gardens, and the gardens of friends to see the wonderful range of June in the maritime Northwest.
June is the month of perennial flowers. Peonies, delphinium, iris, and roses bloom now. Stake tall bloomers like delphinium to keep them from flopping over. You may have noticed during May rains how heavy the large leaves of delphinium become. They are also brittle, so move carefully when setting stakes around them. My favorite stakes are cut from a small stand of black bamboo; the darkness of the bamboo makes them almost invisible when tied in.
Check peonies for symptoms of peony botrytis, a fungal disease that affects leaves and buds, reducing the bud to a brownish dried mass that won't open. Clear away crowded stems of foliage nearby to allow the plant to get good air circulation. The wet conditions of May (and April, March, and February, not to mention January) were unfortunately ideal for the development of this common peony problem. Don't allow any diseased stems to stay in the plant. If peonies aren't planted in full sun, move them to a sunnier location in late fall as they begin to go dormant and the leaves turn red.
All warm-weather loving summer annuals have been slowed but not stopped by cool, wet weather in May. Plant containers of annuals--geraniums, petunias, marigolds, zinnias, and portulaca are colorful summer annuals. All are native to tropical climates, and all appreciate as much sun as you can possibly manage for their location. A hot, exposed western area that gets direct late afternoon sun encourages annual geraniums to grow vigorously.
Container plantings of flowers, vegetables, and herbs need regular fertilizer applications to thrive and produce color all summer. Use any liquid fertilizer, applying about three weeks. Follow label instructions. Some expert container planting specialists apply a half-strength fertilizer (mixed to one-half the label strength) more often, such as every 10 days. Don't overfertilize; too much nitrogen can lead to heavy foliage growth and fewer flowers. Plus, succulent new growth is more likely to be attacked by aphids and slugs. Random over-frequent fertilization doesn't help container plants. Get on a schedule!
Place stakes for dahlias if you didn't when you planted them. Pinch back dahlias and chrysanthemums to achieve sturdy, bushy growth. Remember the motto about chrysanthemums: "Pinch your mum on Mother's Day--and the Fourth of July."
Fuchsias, especially fuchsias in hanging baskets, need attention to watering as days become warmer. They dry out easily, and may need watering once in the morning and once in the evening on days with particularly warm temperatures. To get bushy growth, pinch out the tips of long stringy growth bits, nipping back to a leaf bud. Some growers like to remove faded blooms before they turn to purplish berries; this may prolong blooming.
Water efficiently for all parts of the garden from lawns to shrubs and trees. June days may be cool and cloudy, but seldom does rainfall for the month exceed about an inch-and-a-half. When watering, water slowly and deeply to wet the full root zone. Soaker hoses can work well. After the spring rains, soil is soaked deeply (many of you don't need this observation!) and will respond well to efficient irrigation. Established trees and shrubs, especially those adapted to dry summers, may not need supplementary water. But be sure to water any newly-installed plants for their first one or two years in the landscape.
Keep weeding! Practice weed "birth control," and keep them from going to seed. One weed can produce thousands of seeds, and the seeds can survive for decades in the soil--so be sure to get them before they reproduce. One consolation may be that with long, light evenings, weeding can proceed until nearly 10 p.m.!
Fruit trees such as apples, pears, and peaches will have a normal "June drop," with trees reducing their own crops by dropping hundreds of small green fruits. After this June drop, thin out the crop by removing fruit to leave about six inches between fruit. Plums should be thinned to three inches apart. Fruit trees can survive and produce without thinning, but this process results in the largest and tastiest fruit.
Vegetable gardens may yield their first crops of early planted beets, radishes, and lettuce, though many gardeners got a late start as a result of rains. Peas will be coming in. Be sure to replant as harvests leave garden soil empty; add three pounds of 5-10-10 fertilizer per 100 square feet of garden space after crops come out, before replanting. Thin vegetables to allow enough space for full vegetable development.
Remember to bask in the evening light, appreciating the summer nights, fragrant plants and garden pleasures of June.
Visit WSU's Agriculture Site on the World-Wide Web at http://www.cahe.wsu.edu.