Tidewater Gardening - June 2008
Early Summer Gardening Chores
K. Marc Teffeau
With the garden now in full swing for the season, there are lots of gardening activities to do. Divide spring and early summer flowering perennials such as lilies after the blooms fade. Instead of severing the clump in half, try jiggling the roots apart with two sharp spading forks. This takes more time, but damages fewer roots than cutting the clump apart.
Trim back vines (spring-blooming clematis and wisteria) after they bloom. Prune back the tops of the plants to force out new branches. Gardeners are sometimes confused about proper pruning of their wisteria vines. The two species most commonly grown are Wisteria floribunda (Japanese wisteria) and Wisteria sinensis (Chinese wisteria), both of which bloom before or with the unfolding of the leaves. Pruning wisteria extensively during the dormant season may encourage rampant vegetative growth the next spring. Instead, in June prune out the long, straggly growth except those branches needed for climbing. This is more likely than anything else to induce flowering. Shoots should be cut back one-third to one-half their length. This will induce them to produce the short spurs that will bear next season’s flower clusters. Wisterias are normally vines, but pruning can make them take shrubby and/or weeping forms. Heading back young shoots holds the height at a definite point and after several years, the plant produces a trunk-like stem. Then leaders can be allowed to droop to the ground.
When the foliage of the spring-flowering bulbs yellows, it is time to clean it up. After cleaning up the bulb bed, add your next stage of summer color by setting out bedding plants to cover the bare spots, using care not to damage bulbs. When your early annual flowers are spent, replace them with summer annuals, such as nicotiana, portulaca, zinnia, impatiens, or celosia. Before planting, rework and enrich the soil with compost.
By June a lot of bedding plants at the garden centers look a little ragged; however, you can still get some good deals where the retailer is trying to clean up his/her inventory. Remember that when choosing bedding plants, look for plants that are well proportioned with sturdy stems. Leaves should have a rich, green color. Check for pests if foliage appears mottled or the edges of the leaves are curled. Try to buy packs with large, deep cells spaced far apart, which encourages a larger root system. Also don’t forget to remove old flower heads from bedding plants to prolong the blooming period.
Delphiniums bloom this month. To encourage more flowers, feed the plants after bloom, cut back spent stalks to 1 foot and then remove stalks entirely when new growth is 6 inches or so tall. Unless you like leaning delphiniums, be sure to stake them before they grow tall.
June is also the month for peonies. Peonies are perennial favorites in the flower garden, and few herbaceous plants can rival them for floral display and foliage. Their large, often fragrant blossoms make excellent cut flowers and the foliage provides a background for annuals or other perennials.
Two types of peonies are generally grown in the home landscape – Paeonia hybrids, or garden peony, and Paeonia suffruticosa, or tree peony. Paeonia hybrids are classified according to flower form. All peonies have five or more large outer petals called guard petals and a center of stamens or modified stamens. Single forms have centers of pollen-bearing stamens. Centers of semi-double forms consist of broad petals intermingled with pollen-bearing stamens. Double types have dense centers of only broad petals (transformed stamens). The anemone form, often included in the semi-double category, may have more than one row of guard petals encircling a center of thin, petal-like structures. Japanese types are similar to anemones but have staminodes (stamens that do not produce pollen) in their centers.
In our area flowering usually lasts one week in June to the first part of July. By selecting and planting early-, mid- and late-season bloomers, flowering may be extended for six weeks. Flower colors include all but blue.
Peonies grow from two to four feet in height. Support is often required for tall double hybrids. Peonies thrive in sunny locations and well-drained soils, tolerating a wide range of soil types. Best growth is in soil with a pH range of 6.5 to 7.5, deep and rich in organic matter. Planting, transplanting and dividing peonies are best done in early fall but may be done in spring as soon as soils are workable. Each plant requires an area about three feet in diameter.
Dig a generous hole, large enough to accommodate the roots, and incorporate aged organic matter in the bottom. Place the peony in the prepared hole so that the eyes (small, red-colored buds) are one to two inches below the soil’s surface. Backfill and water well.
Peonies may be left undisturbed for many years. A decline in flower production usually indicates overcrowding and the need for division. Carefully lift the clump and wash away the soil to expose the eyes. Using a clean, sharp tool, divide the clump into sections, each with three to five eyes and good roots. Replant immediately. Recommended Paeonia hybrids in our area include Bowl of Beauty’ - rose pink, Krinkled White’ – white, President Lincoln’ - deep red, and ‘Seashell’ – pink.
If you are growing chrysanthemums, June is the time to disbud the flowers if you want to secure large, beautiful blooms on straight, strong stems. To disbud, remove the small side buds that form in the angles of the leaves along the stems. This allows all food reserves to be used for one large flower rather than many smaller ones. It is still not too late to divide the chrysanthemum plants to produce more plants in the garden. Carefully lift the clumps and divide out the individual plants. Replant them in the landscape where you want to expand your planting. After transplanting, give the plants a good watering with a liquid fertilizer at half strength to give them a little “kick” to get them over the transplanting shock. If they have gotten too tall they can be cut back by about half now to reduce their fall height.
June roses are now in full bloom. A little attention given to your roses now can ensure an abundant supply of blooms through the summer. 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. 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.
If you have noticed odd flower formations on your rose bushes, they may be due to cold temperatures during bud formation. Buds so damaged do not open completely, giving rise to a lopsided flower. Also, as the temperatures and humidity rise, watch for and control black spot and powdery mildew on rose foliage.
In the vegetable garden, consider doing some supplemental fertilizing. Precise placement of fertilizer in the row near the root zone of vegetable plants reduces fertilization costs, does not stimulate between-row weed growth, and may help reduce fertilizer contamination of runoff water. Side dressing, a technique to fertilize established vegetable crops, is beneficial for adding fertilizer when it is most needed by the crop.
If you would like to provide your vegetable plants and efficient and steady feeding of organic fertilizers sink a large can or bucket with many holes in its sides into the soil and fill it about two-thirds full of rotted manure or compost. Rain or occasional watering will keep a rich supply of nutrients seeping out to feed plants in a circle several feet wide.
Cucumbers have a very short “vine storage time.” Under warm, humid conditions, fruits on the vine may remain in prime condition for less than 12 hours. For the best-tasting cukes, pick early and often. The fruits can be stored for up to two weeks at 45 to 50 degrees F and 95 percent relative humidity. Lower temperatures cause chilling damage, and higher temperatures encourage yellowing. Yellowing is also accelerated if cucumbers are stored with tomatoes or apples.
Remove cucumbers by turning fruits parallel to the vine and giving a quick snap. This prevents vine damage and results in a clean break. If you have trouble mastering this, take a sharp knife to the garden for harvesting. Cut or pull cucumbers, leaving a short stem on each fruit.
Remember that the time of day vegetables are harvested can make a difference in the taste and texture. For sweetness, pick peas and corn late in the day. That’s when they contain the most sugar, especially if the day was cool and sunny. Other vegetables, such as lettuce and cucumbers, are crisper and tastier if you harvest them early in the morning before the day’s heat has a chance to wilt and shrivel them.
Yellow crook neck or straight neck squash tastes best when 4 to 7 inches long. Pick when pale yellow (rather than golden) and before skin hardens. Scalloped (patty pan) squash is best when grayish or greenish white (before it turns ivory white) and is still small, even silver dollar size.