Tidewater Gardening - July 2006

Butterfly Bush


K. Marc Teffeau

     A common, easy to grow summer flowing shrub in our area is the Butterfly bush. A.K.A. Summer Lilac, Buddleia or Buddleja, this plant doesn’t require a lot of attention, other than early spring pruning to keep it under control. Butterfly bush is very popular because it does what it is named for. Its flowers attract many different butterflies and bees and is one of the best plants for this purpose.
      Flowers clusters range from 6-to 24-inches long. Flower color ranges from purple, light blue, lavender, reddish-lavender, pink, white, or golden-yellow miniature flowers with orange throats occur densely along a cylindrical to narrow pyramidal, often nodding inflorescence at each stem tip, generally about 6” to 10” long. The fragrant blooms occur heavily from July through August, and continue abundantly until frost if you make a conscientious effort to deadhead the spent flower clusters.
      The plant’s olive-green, simple, hairy leaves have serrated margins and a lanceolate shape that flutter in the slightest breeze lending a fine texture to the landscape. In our area it is grown as either as either a herbaceous perennial or a semi-hardy shrub. Very cold winters can kill the plant back to the ground but it will rebound come spring.
      Buddleia will grow in full sun to partial sun but performs best in full sun in moist, well-drained, fertile soils, but is very adaptable to poor soils, dry soils, and soils of various pH, and is tolerant of heat, drought, and high humidity. Planted in the shrub bed or near a deck or patio in can be used as an accent or border plant to attract butterflies and hummingbirds.
      Butterfly bush can be grown as a container or above-ground planter. Because of its size, however, it is best to give it plenty of room as it can grow 6 to 12 feet in height and spread 6 to 12 feet. A good pruning recommendation in our area is to cut it back to about 1 foot in the early spring to keep the plant manageable.
      There are many different cultivars of Butterfly bush available in the nursery trade. To see a good listing of what is available and to find out how the various colors rate, check out the Longwood Gardens website for their listing of Butterfly bush cultivars.
      July is a good time to do some summer propagation of woody ornamentals. Many plants are easily increased by layering at this time of year. Verbenas, euonymus, pachysandra, ivy, daphne, and climbing roses are some of plants that will root if stems are fastened down on soft earth with a wire and covered with some soil. New, adventious roots will develop from the point of soil contact with the stem. Then, either later on in the fall or early next spring, you can cut the rooted branch off and replant in a new location.
      When pruning away twiggy young growth from rose bushes, make use of the prunings by rooting them and producing new plants. Treat stem bases with rooting hormone, stick them in soil in a cold frame that is out of the sun and water them well. Keep them watered. If some die before rooting, it’s no great loss. Just toss them in the compost, which is where they would have ended up anyway.
      Root holly, azalea, and camellia cuttings in a sand and peat moss mixture set in a cool, shady location. Ivy and periwinkle can be rooted now to fill in any bare spots in your beds. Don’t allow cuttings to dry out.
      If you are one of those adventurous souls who like to keep geraniums over the winter you can make geranium cuttings in late July to start plants for winter and spring indoor bloom. To get flowers in the winter months, you may need to install some fluorescent tubes over the bench or shelves where you grow your plants.
To make cuttings, use the tips of branches about 4 inches long. Cut off the bottom leaves and stick the cuttings about one third their length in a moist, sand-peat mixture. Roots will develop rapidly, and new plants should be ready for potting in about four weeks.
      July is also bug time in the landscape. Most insect pests on ornamentals are not serious enough to warrant control. However the hot, dry in July does bring out red spiders mites. Inspect roses, evergreens, and marigolds in particular for pale-green coloration. Hold a white sheet of paper underneath a leaf and briskly tap it. Tiny, crawling mites will drop onto the paper if they are present on the leaf. If infestation is light, discourage mites with a forceful, direct spray of water from the hose. Severely infested annual plants should be removed and destroyed. Mild infestations can be controlled with an insecticide like Safer’s soap or similar bio-rational material.
      Japanese Beetles are always a pain this time of year. A non-toxic approach to Japanese beetles is to remove all flower blossoms as soon as they begin to fade and all fruit as soon as it is ripe. Japanese beetles are especially fond of overripe fruit and deteriorating flower blossoms.
      After taking these preventive steps, go out to your garden daily and knock the insects off their perches and into a wide-mouthed jar of soapy water. That will gum them up and prevent them from flying away. I would not recommend the Japanese beetle traps unless you place them well away from any landscape plants. The scented lure attracts them and you don’t want to encourage these pests to stop and munch your roses or grapevines on their way to their demise.
      Chrysanthemums should be lightly fertilized every two weeks with a water soluble fertilizer. To keep plants compact and full of blooms, pinch out new tip growth until eight weeks before they are to bloom, approximately mid-July. For large exhibition mums, allow only one or two shoots to develop. Stake these shoots, and remove side buds as they start to develop.
      Divide and transplant bearded iris using the vigorous ends of the rhizomes. Discard the old center portion. Cut the leaves back to about 8 inches.
      Propagate bleeding heart and Oriental poppy when growth has stopped and foliage has disappeared, indicating a dormant condition. Dig up a root and cut it into 1 to 2-inch pieces. Plant root pieces in a mixture of sand and rich loam. Keep the soil fairly moist, and soon tiny leaves will shoot up. The new plants will be ready for permanent quarters in the spring.
      While you are busily enjoying harvesting the vegetable garden don’t forget that you can prolong the season. Start your broccoli, cabbage, and cauliflower seeds now so you can set them out as fall transplants in August. It is difficult to locate fall vegetable transplants in this area as most greenhouse growers are oriented to the spring season.
      Mid to late July is a good time to direct seed lettuce, spinach, beets, carrots and turnips into the garden. They may be a little slow in germinating because of the high temperatures. Try lowering the soil temperatures by covering the seed bed with a floating row cover like “re-may” or some other shading material.
      Succession plantings of green beans can go in until the first of August and do another seeding of summer squash to replace those plants infested with squash borers. Wait until August for the fall planting of peas.
      Happy Gardening!!!