Sometimes your garden needs something tall, something blue. The abundant display of summer perennials laden with yellow daisy-like flowers begs for plant selections which offer dark contrast.
A “temperennial” here in zone 6, Tall Mexican Petunia won’t winter over outdoors for us, but it certainly will in zones 8-10. Still, we always make room for it in our gardens and also use it in container combinations where the tall 3-4′ purple stalks are clothed with narrow dark green purple tinted foliage. The continuous display of violet blue funnel shaped flowers extend on short stems from the leaf axils, and attract bees, butterflies and hummingbirds.
Ruellia ‘Purple Showers’ does enjoy evenly moist soil, and will even grow well along a pond?s edge or in low standing water, a situation that can be challenging. This does not mean it won?t grow in average soil conditions, for it will, but it does not want to fry. Southern nursery catalogs list Ruellia as an evergreen shrub. We suspect Ruellia may become territorial in warm climates, and should be planted where its vigor is an asset.
Not all Persicaria deserve persecution. Persicaria amplexicalis ‘Golden Arrow’ is not only one of the “good” members of the Polygonum (Knotweed) family, it is an extremely handsome and versatile perennial. The first thing you should note is the golden green lance shaped foliage, which is attractive all season. Big plus. In mid summer ‘Golden Arrow’ begins to display an array of ruby colored spiky tassels, which account for its common names: Firetail and Red Bistort. The flower show continues into September, and both flowers and foliage combine beautifully with the many late summer yellow composites, as well as pink or blue/violet asters, and of course all the Salvia.
Leaf color is brightest yellow when grown in full sun, but ‘Golden Arrow’ will require a little extra moisture if the area is on the dry side. Otherwise, grow it in a well drained soil in half day sun, where the golden yellow will tint slightly more green. Foliage height reaches 18-24″, with flowers adding another 6″ or so to the plant’s stature. The spread of each plant depends on age and culture, but expect Persicaria ‘Golden Arrow’ to eventually take up 2 sq. ft. It grows well in a wide range of hardiness zones from relatively mild zone 9 through a quite chilly zone 5.
Japanese Clethra is waiting to be discovered. It is a plant for all seasons, boasting fragrant mid summer blossoms, yellow-orange to red fall foliage, and exfoliating bark in winter. If left unpruned it will grow as a multistemmed shrub or small tree, but we prefer to see it trained to a single leader, with lower limbs removed, so that the showy bark can be better appreciated.
We were smitten when our young plant came into bloom in July. Trios of sweetly scented white, 4-6″, twisting racemes will drip from the branches into August. The ovate serrated foliage, in a shade of dark green, really sets off the white blossoms. Fall color is also striking, ranging form yellow orange to deep red. Although Clethra barbinervis is fast growing, it seems to reach an ultimate height of 15-20′. It prefers a well drained, neutral or slightly acidic soil with adequate moisture. Clethra barbinervis grows well in partial shade, although it will tolerate and bloom abundantly in full sun, if watering needs are met. It can be cultivated in zones 5-8.
Hayes Starburst Hydrangea is a floral arranger’s dream. This chance discovery, by Hayes Jackson of Anniston, Alabama, differs from the species by its showy display of clustered greenish white, multi sepaled star shaped flowers. It is a form of Hydrangea arborescens, also known as Smooth Hydrangea or Hills of Snow, and although native to the southeastern U.S., is cold hardy into zone 4.
Hydrangea arborescens ‘Hayes Starburst’ blooms on new wood, so there is little danger of winter damage to flower buds. We recommend cutting back the woody stems to 12″ in early spring to keep the plants tidy. Hydrangea arborescens prefers to grow in full to half day sun and in a well drained soil that still gets adequate moisture. If there is a common complaint about this species it would be that the flower clusters are so heavy that they weigh down the supporting stems. Some consider this an addition to the plant’s charm, and if it is sited on a slope or above a retaining wall, you could take advantage of its cascading habit. If an upright habit is preferred, situate a large tomato cage over the cut back stalks in spring, which will lend support. The height and spread of this shrub can remain a manageable 3′ x 3′, if pruned annually.
First, we fell in love with the foliage. The new foliar growth is a delicious shade of caramel pink, gradually becoming lime green as the summer progresses. As the July heat intensifies, 4-6″ panicles of white pearly buds burst into creamy Astilbe like plumes. Sorbaria sorbifolia ‘Sem’ is a compact growing False Spirea, growing only to 48″, unlike the species which can reach 8′ or more. ‘Sem’ will give you moderate height without obscuring your view. Yes this form will sucker and form a thicket…but that is why you should use this shrub as a low hedge, or for filling a space that you don’t want to fuss over.
Here are the other pertinent facts: Sorbaria ‘Sem’ grows in full sun or part shade, is deer resistant and is hardy to minus 35 degrees F. Pretty and tough, don’t you think?
Begonia, Pilea and Tahitian Bridal Veil
Again, it is so much about the foliage. The angel wing leaves of Begonia ‘Sinbad’ are really a soft celadon green veined in rose, but have a silvery cast. On close inspection, the silvery effect is due to the pebbly texture formed by the tiny raised white leaf segments. Simple, sweet pink flowers dangle from the leaf axils. For filler, the tiny white variegated foliage of little Pilea, commonly called artillery fern, creates a frothy effect beneath the bolder leaves of ‘Sinbad’ and the casual abandon of Gibasis geniculata , also known as Tahitian Bridal Veil, with its two tone green/purple foliage and white baby?s breath blossoms finish off the combination.
Culturally, use a well drained potting soil, amended with Osmocote. Begonias do not want to live in soggy soil, so monitor watering by allowing the soil to dry out a bit. This ensemble would enjoy morning or filtered light, and would be a suitable arrangement for a covered porch, where the minimal watering needs can be monitored.
Expand your repertoire of container plants for shady situations. Little variegated Pilea also known as Tricolor Artillery Fern has dainty white variegated leaves, often tinted pink, which are displayed in a spray like fashion on fleshy succulent stems. Plants grow to a height of perhaps 6″ spreading to 8-10″ and work as an airy filler in container combinations. Often sold as a selection for terrariums, Pilea prefer a sunny window if grown indoors, but outside, bright shade seems to be its perfect growing situation. She needs little care except as needed watering.
Remember when Coleus was disdained by “serious gardeners” just 20 years ago? Until recently Succulents also seemed to get a bum rap. Perhaps it was because of the silly little dish gardens offered in discount stores, featuring a ubiquitous strawflower glued onto a poor little cactus. We decided quite some time ago to treat succulents with dignity. Their foliage offers an array of subtle and strong desert colors and textures which inspire us with ideas for endless combinations. And, they couldn’t be easier to take care of– perfect container plans for the summer weekend home, since so little water is required.
Begin your ensemble by selecting a handsome container. Break the rules…why not use a fancy bowl or urn that you would use for traditional annuals? Shallow pots are always fine and suitable, but deeper pots can certainly be used if you fill them with a very sandy, fast draining soil. Do not use a moisture retentive peaty potting mix, for it will easily become water logged if we have extended wet weather. You can use a light dose of fertilizer in your soil mix, but don’t over do it.
Select a variety of foliage shapes and plant forms, such as the rosettes of Echeveria, the trailing stems of Delosperma and the fine texture of tiny Sedum. We always find that packing the container with plants gives immediate gratification, and the plants will not suffer as they require little nutrition. Early autumn will bring changes to your composition, as the fall foliage colors intensify and many succulents begin to flower. Before a freeze, bring your succulents indoors. They winter over easily on a sunny window sill.
This easy care combination, which will be very happy in a spot that receives 4-6 hours of sun, includes Fuchsia ‘Gartenmeister’ complimented by multihued Calibrachoa ‘Tequila Sunrise’, Helichrysum ‘Limelight’ for light contrast, and Coleus ‘Dipt in Wine’ which picks up the colors of the other 3 candidates.
The Fuchsia and Calibrachoa (Million Bells) will lure hummingbirds and bloom endlessly. Should the Helichrysum (Licorice Plant) or Calibrachoa exceed their bounds with vigorous growth, just clip back. Plant this grouping in a good quality potting mix amended with compost or PlantTone, and Osmocote. In addition to fertilizer in the mix, we always recommend liquid feeding your containers every 1-2 weeks with a balanced plant food, such as Dyna Gro.
A classic combination for a sunny spot. We’ve combined our favorite Pelargonium sidoides with a new heat tolerant pale pink Marguerite, Argyranthemum ‘Pink Reflection’, silvery Centaurea gymnocarpa ‘Colchester White’ and Dichondra ‘Silver Falls’ and a compact selection of Gaura ‘Belize‘, with wine tinted foliage and wine/pink blossoms that dance on 18-24″ stems all summer.