Tidewater Gardening - June 2013

Jumping Into Summer


K. Marc Teffeau

After going through a somewhat soggy and cool spring we have now arrived in June! One nice result from temperatures being about 10 degrees colder than normal for the end of April and early May was that the flowering shrub display lasted a lot longer than normal. Some azaleas and dogwoods held their flowers for almost two weeks.
What to do in June? There are plenty of gardening activities to keep you occupied. The early peas you planted should be ready for harvest, along with greens like lettuce and spinach. Now is the time to transition to warm-season crops like peppers, tomatoes, eggplants, cucumbers, sweet corn and squash.
When you finish cutting the broccoli, and the plants start to bolt (flower), pull them out and replant with zucchini or yellow-necked squash, or do a seeding of green beans.
I always have a problem with squash vine borer in the zucchini, even though I spray with an organic repellent. To compensate for some damage, I make additional plantings about three weeks apart.
Stop cutting asparagus in mid to late June when the spears become thin. After the last cutting is made, fertilize by broadcasting a 10-10-10 formula at the rate of 2 pounds per 100 square feet. Allow the tops to grow during the summer to store food in the crowns (roots) for the crop next spring.
A last vegetable gardening tip: for very efficient, steady feeding of vegetables, sink a large can or bucket with many holes in its sides, into the soil and fill it about 2/3 full of rotted manure or compost. Rain or occasional watering will keep a rich supply of nutrient seeping out to feed plants in a circle several feet wide.
In the landscape we now shift to maintenance mode. Remove old flower heads from annual bedding plants to keep them blooming. Disbud chrysanthemum flowers to secure large, beautiful blooms on straight, strong stems.
To disbud, remove the small side buds along the stems that form in the angles of the leaves. This will allow all of the food reserves to be used for one large flower, rather than many smaller ones.
You can still plant annual flowers in tubs or large containers for the porch or patio. Make sure there are holes in the container’s bottom to provide good drainage.
June is the time to remove foliage from spring bulbs after it turns yellow and begins to dry. Carefully plant bedding plants to cover the bare spots, using care not to damage the bulbs.
In your iris bed you should leave the foliage alone, but cut the flower stalks down to the crown when they have finished blooming. If your iris are over-crowded, now is the time to lift and divide them. If your iris have iris borer larvae in the stems or rhizomes, the leaves and flowers stalks may wilt. The best control is prevention.
To prevent a borer attack, do not mulch your irises. Plant rhizomes high in the planting bed and select full-sun sites. If you suspect borers, dig up the rhizomes after bloom, cut off rotted and infested portions and replant.
Attract beneficial insects to your landscape by planting a wide variety of flowering annuals and perennials that will bloom over the entire growing season. Good choices are plants in the following families: daisy (marigolds, daisies, asters, mums); carrot (dill, fennel, anise, yarrow, parsley); and mint (all mints and thymes).
Pinch out the blower buds of fall bloomers like asters and goldenrod to keep the plants bushy and prevent early flowering.
Spring flowering shrubs such as spirea, viburnum, lilac and forsythia should be pruned as soon as they are done blooming. In fact, mid to late June is an excellent time to take softwood cuttings of shrubs to start new plants. June is still a good time to plant shrubs in the landscape if you give them some extra attention.
If you do not have much room to landscape, consider using some of the many dwarf varieties available. These are plants that have slow growth and stay small, so there is little pruning maintenance. There are numerous dwarf evergreens, flowering trees and shrubs from which to choose.
When you buy nursery stock that is container grown, 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 planted in the ground.
While we are focusing on outdoor activities, do not forget about your houseplants. Begin fertilizing your indoor plants now that they are actively growing again. If you usually take your houseplants outdoors for the summer, be sure to keep them out of full-sun locations until they are fully acclimated to outdoor conditions.
A nice use of your houseplants outdoors is to combine them with flowering annuals in container plantings. The various green foliage hues of houseplants and different leaf forms provide a nice contrast to annual flowers.
You should check for insect problems in houseplants that are outside on a regular basis. Hose them down regularly if you notice spider mites.
Insects can also be a problem if the plants are left indoors. Check them for mealy bugs, spider mites, aphids, whitefly and scale. If spider mites are a problem, consider spraying them with a labeled horticultural oil or soap and pyrethrum mix. If the plants are large, do your spraying outdoors.
Last month we discussed creating an edible landscape. An alternative landscaping approach is to use wildflowers in various fashions. The National Garden Bureau has declared 2013 as the “Year of the Wildflower.”
As the NGB notes, wildflowers can be used anywhere. In the home landscape they are ideal for creating colorful beds and borders, as well as offering a lower-maintenance alternative for large areas or replacing turf grass.
Wildflowers can be planted to cover large, open areas or assist in the recovery of a landscape that has been damaged or destroyed by the actions of people, a natural disaster, or the spread of invasive plants.
Of course, one of the debates is “what is a wildflower”. Various definitions apply depending upon your horticultural perspective. I used to say that a perennial is a wildflower with a pedigree.
One definition is a plant that was not intentionally seeded or planted and grows without cultivation. Another definition is that a wildflower is any plant growing without the help of man, regardless of the plant’s country of origin. Still others define a wildflower as a plant found in a specific geographic area that was grown from seed or plants also from that area. No matter how you define them, wildflowers can beautify any landscape.
Some of the wildflowers are native species found here before the Europeans came over. Others were brought here by the various immigrant groups. In fact, many of our favorite wildflowers have been growing in European gardens for centuries. Even some of our native wildflowers enjoyed more popularity in Europe than in the U.S. where they went unnoticed by gardeners.
In England, informal and wildflower gardens became fashionable in the 1870s. Wild gardens featured hardy, herbaceous plants, including both native and exotic species. They were designed and placed where they would thrive with little additional care.
There are a number of wildflower species that can be planted in the landscape, either in beds, borders or larger plantings. The NGB notes that Purple coneflower (Echinacea purpurea), California poppy (Eschscholzia californica), columbine (Aquilegia canadensis), butterfly weed (Asclepias tuberosa), and black-eyed or brown-eyed Susans (Rudbeckia triloba and R. hirta) are among the popular wildflowers planted by American gardeners, all of which happen to be native to the U.S.
Purple coneflower is native to the Midwestern prairies and the dry, open woods of the Southeast, but can be found in gardens from Maine to California because it is fairly adaptable to most types of soil and does well, even in dry conditions. Plants flower from late spring to early fall attracting butterflies and bees to the large, purple, daisy-like flowers. After the long-lasting blooms drop their petals, the distinctive seed heads develop and provide food for goldfinches and other birds.
When Echinacea is mentioned, most gardeners automatically think purple, or shades of purple. First-year flowering of a new Echinacea hybrid, Cheyenne Spirit, provides sought-after shades of red, orange, purple, scarlet, cream, yellow and white. For 2013 the All-American Selections folks have designated Echinacea ‘Cheyenne Spirit’ as one of their winners.
Cheyenne Spirit does great in our garden area with a blooming season from late spring through autumn. According to the breeder, Kieft Seeds, Cheyenne Spirit overwinters well, is a drought-tolerant plant, and provides a great flower display in the first year. Because of its branding structure, this compact plant does not topple over during wind and rain like many Echinacea. As an added bonus, this maintenance-free Echinacea doesn’t even need deadheading to provide summer-long beauty.
All Echinacea should be planted in full sun with well-drained soil for best overwintering performance and it has a wide range of uses from the perennial border, in a mass landscape planting, in a butterfly garden, or as a cut flower.
Happy gardening!

Marc Teffeau is the Director of Research and Regulatory Affairs at the American Nursery and Landscape Association in Washington, D.C. He lives in Preston with his wife, Linda.