GreenGardeningStL.com

By Cindy Gilberg

Missouri is home to a long list of native shrubs and small trees, many of which are prime choices for our landscapes. According to Don Kurz (author of the field guide “Shrubs and Woody Vines of Missouri”), approximately 130 species of small to medium native woody shrubs can be found growing in our state. While this doesn’t include several of the small trees, some are species we might think of as small trees rather than as shrubs. There is a fine line distinguishing between small trees and shrubs – in general, trees have single trunks and are about 20 feet or more in height while shrubs have multiple stems. Of course, gardeners sometimes confuse the situation even more by encouraging multiple stems on small trees and by pruning shrubs into single-stem specimens.

As versatile as they are functional, this group of plants is an integral part of the overall landscape, adding medium-size, year-round structure. Between the canopy of large trees and the herbaceous plants that form the ground layer, shrubs and small trees provide the framework or backbone of the garden. In this way, they are useful in outlining the structure of a space. Many designers use them to create ‘rooms’ within a garden as well, providing enclosure and privacy.

Shrubs and small trees are quite valuable as screening and are an aesthetic alternative to fencing, especially when the fence is not tall enough to successfully block the view. Consider combining groups of different species with varying heights and textures for a more dynamic setting. Repetition of similar forms throughout the view creates rhythm and serves to tie the garden together visually. A few species that work well for screening are hazelnut (Corylus americana), black haw (Viburnum prunifolium), gray dogwood (Cornus racemosa), and ninebark (Physocarpus opulifolius). These species are also outstanding choices for planting after invasive honeysuckle is removed, particularly when the invasive bush honeysuckle is functioning as a screen.

Smaller shrubs (three to five feet) can be planted in large masses to form tall ground cover, making a handsome backdrop for shorter herbaceous perennials. A classic look is to have small trees rising up out of these masses, using the ground cover shrubs as an anchor for the scene. A useful list for this situation includes fragrant sumac (Rhus aromatica ‘Grow Low’), beautyberry (Callicarpa americana), wild hydrangea (Hydrangea arborescens) and golden currant (Ribes odoratum).

Fragrant sumac - Rhus aromatica ‘Grow Low’

All of these plants can be used as accents in the garden where textural contrast is needed or to punctuate a view. Leatherwood (Dirca palustris) is a lesser known beauty that is slow-growing, reaching an ultimate height of five to six feet. Vernal witch hazel (Hamemalis vernalis) blooms in late winter with dark-yellow flowers that are delightfully fragrant while common witch hazel (H. virginiana) blooms with lemon-yellow flowers in late fall. Both grow 12 to 15 feet tall but give vernal witch hazel lots of space since it grow 15-20 feet wide as well. Both have desirable yellow-orange fall foliar color.

Golden currant - Ribes odoratum

Remember that habitat for birds and other wildlife is best accomplished with a diversity of plants. Make note of when a plant flowers, attractive for both the gardener and pollinating insects. Many have berries, such as dogwoods, viburnums and spice bush (Lindera benzoin), providing additional interest in the garden as well as food for birds. Dense branching of shrubs and small trees also offers cover and potential nesting sites for many birds.

Most gardeners know the classic ‘top ten’ that include dogwood, redbud, serviceberry, fringe tree and winterberry. Just a handful of other worthy options for the landscape are discussed here. The Native Plant School, held at Shaw Nature Reserve, has a new three-part class this year – Native Small Flowering Trees and Shrubs. This is a wonderful way to become familiar with a whole new palette of hardy native plants.

Cindy Gilberg, horticulturist and Missouri native, founded and ran the garden center at Gilberg Perennial Farms with her husband Doug for 28 years, also teaching classes and workshops on gardening and garden design. She now focuses on garden design, consulting and teaching, and also works part-time in the Whitmire Wildflower Garden at Shaw Nature Reserve, emphasizing the use of native plants in home landscaping.

By Cindy Gilberg

Most gardeners think of winter as down time. The only thing that’s down are the leaves, allowing the opportunity to view the more subtle beauty of the garden. Look outside your window. What do you see? Perhaps a better question would be what don’t you see. Yes, gone are the colorful flowers of spring and summer. Is color missing from your winter garden? Get to know some of our native shrubs and trees that have bountiful crops of berries in the fall and winter months. Adding these into your landscape will provide the sparks your garden may need in this season.

These native plants produce autumn crops of berries with the sole purpose of attracting birds and small mammals. Animals depend on this late fall and winter source of food and the plants depend on the animals for seed dispersal – it’s a win-win situation. Because of this relationship, the berries are noticeable and colorful. Additional color and animation will be introduced into the garden in the form of Missouri’s many winter songbirds that forage for these small fruits.

Winterberry - Ilex verticillata

Perhaps the best known is the deciduous holly, also called winterberry (Ilex verticillata). Many horticultural cultivars have been introduced in recent years including ‘Red Sprite’ (a dwarf form), ‘Winter Red’ and ‘Winter Gold’. The native winterberry is spectacular, sporting many brilliant, red clusters of berries on its branches from late fall through the winter months. It forms a dense shrub that can grow to twenty feet or so.

The possum haw (Ilex decidua), a close relative of winterberry, is a multi-trunk, small tree that grows taller, to a height of about thirty feet. This is the more commonly encountered species in Missouri. In appearance and culture, possum haw is very similar to winterberry.

Yet one more Ilex, though wild populations are rare, is the American holly (Ilex opaca). The red berries are set against evergreen leaves making it doubly attractive and quite desirable in the winter landscape. Hundreds of horticultural varieties of this species exist and its branches are a common and welcome sight during the winter season.

All hollies (Ilex) tend to be dioecious, meaning the plants are either predominantly male or female. To ensure an abundant crop of fruit, locate a male plant in close proximity to the female plants. The various species are similar in their cultural requirements – they prefer an average-to-moist location and are tolerant of light-to-partial shade locations.

Hawthorns (Crataegus) are members of the rose family (Rosaceae) and are represented in Missouri with up to fifty naturally occurring species. The downy hawthorn (Crataegus mollis) is the official state flower of Missouri. All hawthorns have clusters of white rose-like flowers in mid-spring and can be quite showy. Like their cousins, the roses, all have thorns so use caution if you are in the pruning mood. It is in the fall and winter months that these small (to twenty feet) tough trees show off with bright orange or red berries. These fruits, not tasty when eaten raw, do make excellent jam or jelly if the birds don’t beat you to them. Native populations of hawthorns are typically found in open woodlands (light to partial shade) and are tolerant of average, dry soil. One of the hawthorns however, the green hawthorn (C. viridis), occurs naturally in low, wet areas and so grows happily in moist soils.

Wahoo - Euonymous atropurpureus

Most gardeners associate the name Euonymous with the evergreen ground cover that has lost popularity and become a nuisance in recent years. Yet Euonymous atropurpureus, known as wahoo, is not only fun to say but also an intriguing plant in the garden. In early fall, pink capsules appear, suspended on long stems like dangling earrings. After the first frost, these capsules pop open to reveal the scarlet fruit. Wahoo will sprout from the roots and produces a multi-trunk shrub-like form. This thick suckering habit makes it useful as a hedge in light shade. Growing naturally on wooded slopes and along streams, it is at home in the shade garden in both dry and moist soils.

So next time you meditate over a cup of coffee and gaze at your garden, imagine some of these native plants embellishing the winter scene. Imagine also the abundance of birds outside your window, enjoying a profusion of natural foods.

Cindy Gilberg, horticulturist and Missouri native, founded and ran the garden center at Gilberg Perennial Farms with her husband Doug for 28 years, also teaching classes and workshops on gardening and garden design. She now focuses on garden design, consulting and teaching, and also works part-time in the Whitmire Wildflower Garden at Shaw Nature Reserve, emphasizing the use of native plants in home landscaping.

By Cindy Gilberg

Outside my window is a constantly moving and colorful avian dance. Hummingbirds are tenaciously defending their nectar sources and will do so until their departure in October. Goldfinches hang onto coneflowers as they extract the seeds they love so much. Bluebirds and Phoebes swoop down to capture various insects. As the days get shorter signaling the last hoorah of summer, a multitude of birds begin their long migrations southward. Our region is on a major flyway for many of these travelers who visit us for brief periods in the fall and again in the spring. Numerous other bird species are either year-round residents or come to stay for the winter months.

Recognizing basic needs such as food, water and shelter and providing those needs year-round is important. Diversity of plants in your garden is the key to ensuring that a diversity of our feathered friends will visit. Water gardens, with small, shallow rivulets or waterfalls, provide water and additional habitat for birds and an pleasing garden feature for the gardener. A very small percentage of birds actually visit birdfeeders and most prefer natural habitat that favors their needs.

The smorgasbord should include plants that provide seeds or berries and a habitat conducive to insects, a favorite food of many birds in the summer. Deadheading flowers is a common practice for many gardeners but prevents nutritious seeds from ripening. Avoid using insecticides (harmful to birds too!) and allow the birds to be part of your biological control program. After the first frost don’t be so quick to clean up the garden. Pruning perennials to the ground not only removes both seed and cover for many birds, it can also cause crown damage or winter kill in many perennials.

One of the most popular birds is the ruby-throated hummingbird. They arrive in April when the wild columbine (Aquilegia) and bluebells (Mertensia) are blooming in our woodlands. These quick-flying, diminutive gems that frequent our gardens are especially attracted to tubular-shaped red, orange and pink flowers that provide nectar. They dart about for nectar, returning again to the shelter of large shrubs and trees, so include some in your garden design. Provide favorite nectar sources such as blazing star (Liatris), beebalm (Monarda), Phlox and catchfly/pinks (Silene). Larger plants, for example, red buckeye (Aesculus pavia) and trumpet creeper (Campsis), are among other desirable nectar sources.

The Gateway Gardener "Petite Prairie" garden is a bird haven, with coneflowers, rudbeckia, milkweeds, Joe pye and many other bird-butterfly-bee-attracting native plants.

Prairie and savannah plants appeal to a wide array of birds such as wrens, sparrows, cardinals, finches and my favorite – the indigo bunting. Blazing star (Liatris) is at the top of the list again, inviting numerous butterflies when in bloom and then birds that nibble at the seeds. Plant an assortment of flowers from the aster family, the most familiar being Aster, coneflowers (Echinacea), black-eyed Susans (Rudbeckia), goldenrods (Solidago) and sunflowers (Heliopsis/Helianthus). Grasses add unique form and texture to the garden as well as an abundance of seed. Little bluestem (Schizachyrium), prairie dropseed (Sporobolis) and side oats grama (Bouteloua) are wonderful additions to garden designs.

As autumn turns to winter insect populations decline and many birds shift their diet to fruits, most commonly provided by shrubs and trees. Migrating birds such as orioles and tanagers search for high-fat fruits offered in fall by dogwoods (Cornus) and spicebush (Lindera). I love watching the large flocks of cedar waxwings visit our cedar trees (Juniperus) to eat the frosty blue berries. Hawthorn (Crataegus), blackgum (Nyssa) are other welcome additions in any garden setting. To complete the garden design add some shrubs, most notably winterberry (Ilex), Viburnum and Sumac. All of these have attractive fruit that create winter interest in the garden.

Look over the plant lists for attracting birds and notice that many plants attract more than one group of birds in different seasons. Incorporate any or all of these plants into a conventional sunny garden design or looser more natural design – either way you will notice an increase of avian visitors.

Cindy Gilberg, horticulturist and Missouri native, founded and ran the garden center at Gilberg Perennial Farms with her husband Doug for 28 years, also teaching classes and workshops on gardening and garden design. She now focuses on garden design, consulting and teaching, and also works part-time in the Whitmire Wildflower Garden at Shaw Nature Reserve, emphasizing the use of native plants in home landscaping.

By Cindy Gilberg

The seed is hope; the flower is joy.
- Author Unknown

The cooler days of autumn are incredible for taking a walk through the garden or the prairies and woodlands at Shaw Nature Reserve. At this time of year the last bits of color fade to reveal the ripening seed heads of late-summer and fall-blooming perennials such as aster, goldenrod and late blazing star. Native grasses are full with fat seeds, causing them to bend over and sway in the wind. Seeds, those marvelous little parcels of hope for next year’s bounty in the garden, are everywhere. Goldfinches and other birds are taking advantage of this important fall and winter source of food.

Why bother to collect seeds? One major reason is the satisfaction of growing your own plants to expand your garden. Because many native plants, such as butterfly weed, have deep tap roots, it is much easier to start new plants from seed than to try to dig and move or divide them. Besides, it is illegal to dig plants in the wild. Another wonderful reason is to share them with other native plant enthusiasts.

Getting to know your plants’ bloom time will give you an indication of when to begin collecting seeds. The early- to mid-spring-blooming natives form their seeds beginning in late April through May. And so, in a regular progression, other later-blooming plants begin to form ripe seed, typically within four to six weeks after their flowers have faded. Take the time to be observant and take notes so that next year you will have a “heads up” as to when to look for your favorite seeds.

Don’t be impatient – be sure to wait and collect seed that is ripe. Unripe, green seeds will not ripen on their own after being cut from the plant. To determine ripeness note the color of the seed since immature seed heads are very green or there is still color in their flower petals. Wait until petals fade completely and the seeds turn tan or brown. September through November is when plants such as goldenrod, aster, ironweed and blazing star turn a dark russet color and begin to appear “fluffy,” indicating that they are ripe and ready to fly away on the first winter wind.

Collect seed when the weather is dry. Avoid the morning dew, waiting instead for mid-morning or later after the sun has begun to warm and dry the seed heads. If seed heads are moist, you run the risk of spoilage due to mold. Seed heads can be cut into paper bags or placed into cardboard flats to insure that sufficient drying takes place. Once dry, the seed separates easily from the plant tops, capsules or pods depending on what you collect. Shake the bag and separate the seed from the chaff. A sieve or screen is quite useful at this point. Once the seed is fairly clean, it should be placed in a mixture of moistened potting soil and sand (50/50) in a ziplock. Mark the name of the plant and the date you collected it on the bag, then store it in the refrigerator or other cold place for three months. This process, known as stratification, mimics the natural cycle of winter. In the spring, the seeds can be sown either into pots or directly in your garden, ready for the new year.

An option would be to sow the clean, dry seed directly into the garden in late November and December, thus freeing up sometimes-valuable space in the refrigerator. The drawback to this method is that you might be providing a wonderful meal for foraging birds and rodents in the winter and it is sometimes difficult to identify seedlings in the spring. A wonderful little book that can help you with identification is Seedling ID Guide for Native Prairie Plants. It is available at the Visitors’ Center at Shaw Nature Reserve and at Missouri Department of Conservation – Powder Valley in Kirkwood as well as on their website, MDC Nature Shop. So far there is not a printed book on woodland seedlings or others you may collect so it is a great idea to photograph those seedlings as they come up in pots and keep them for future reference.

Remember to only harvest what you need – don’t be greedy. Unless you have an acre or more to seed, try to leave a lot of plant tops with seeds to provide food for overwintering birds and small mammals. Don’t cut the dying foliage to the ground since it is a source of shelter small animals. A close look will reveal chrysalis and cuccoons, egg cases of mantids and other overwintering insects.

If you feel there is enough for everyone, note that the dried seed heads are also quite fascinating subjects for dried arrangements.

Keep seed collecting in mind next spring as you see other plants you want to add to your garden. Starting in late April-May, woodland wildflowers such as wild geranium, bellflower and sweet william begin to ripen. Go ahead and collect, clean and store those seeds in the refrigerator. Keep them there until late November for sowing outside. Or leave the seeds in your refrigerator through winter and sow in early spring for another year’s bounty.

Cindy Gilberg, horticulturist and Missouri native, founded and ran the garden center at Gilberg Perennial Farms with her husband Doug for 28 years, also teaching classes and workshops on gardening and garden design. She now focuses on garden design, consulting and teaching, and also works part-time in the Whitmire Wildflower Garden at Shaw Nature Reserve, emphasizing the use of native plants in home landscaping.