The Ornamental Garden in February
February may be the shortest month of the year but, for die-hard gardeners, it seems to drag on forever. Perhaps that’s because we long to feel warm sunshine and spring breezes on our faces. At this time of year, we hunger for the first glimpse of new leaves pushing through the soil and the scent of rich earth awakening from its winter slumber. But spring is yet a month away and winter still holds its icy grip on us. In the meantime, we bide our time daydreaming about new plants to try, old plants to divide, and new gardens to design. Ornamental gardening is an on-going process. So use this month wisely to both dream and plan.
PROJECTS TO DO OUTDOORS IN FEBRUARY
Cut back dormant ornamental grasses. New growth will begin sooner when the old foliage is removed. The easiest way to cut back large clumps of dormant grasses is to tie a bungee cord around the clump and use an electric hedge trimmer to cut it back to a few inches above ground. For smaller dormant grasses, such as Japanese forest grass (Hakonechloa) or Muhly grass (Muhlenbergia), use hedge clippers to cut them back to about 3 to 6 inches. Try not to cut too close to the crown. Otherwise, moisture may settle in the crown causing it to rot. Small evergreen grasses, such as sedge (Carex), blue oat grass (Helictotrichon), lily turf (Liriope), and mondo grass (Ophiopogon), may not need to be cut back. Instead, some of the old spent growth may be pulled out by hand. If that method doesn’t work and you do need to cut the old growth back, cut by about two-thirds. The plants may look as if you gave them a Mohawk haircut, but new growth will cover up the cuts. Again, avoid cutting too close to the crown.
Prune dormant trees and shrubs – In general, late winter is the ideal time to prune trees and shrubs before they start actively growing. However, the right time of year to prune depends on the species of plant and the reason for pruning it. The Virginia Cooperative Extension (VCE) has a number of helpful publications that can help take the mystery out of pruning. For example: Pruning Basics and Tools, Deciduous Tree Pruning Calendar, Shrub Pruning, Shrub Pruning Calendar, and Evergreen Tree Pruning Calendar. For these and other VCE publications on pruning, see the James City County/Williamsburg Master Gardeners’ Pruning Handbook. Meanwhile, here are a few general pruning guidelines:
- Branches or limbs that are dead, damaged, or a safety hazard may be pruned any time of year.
- Deciduous trees and shrubs that require heavy pruning should be pruned in winter while the plants are dormant.
- Deciduous trees and shrubs that only need a light shaping may be pruned in the summer. Some trees such as maples and yellowwoods heavily bleed sap when cut. Research the species first for information on the proper time of year to prune it.
- Conifers (evergreens) generally don’t require pruning except to remove dead or damaged branches, remove multiple or weak leaders, or correct structural defects. However, should you find it necessary to prune a conifer, do not cut back into old wood having no leaves or needles. Conifers don’t form new buds on old wood, so prune only green, pliable new growth. Consult VCE Publication 430-461, Pruning Evergreen Trees for additional information on pruning conifers and other evergreens.
- Spring or summer-flowering shrubs that bloom on last year’s wood may be pruned within a couple of weeks after flowering is finished. If you prune later than that, you may risk losing next year’s blooms.
- Fall is never a good time to prune because it encourages new growth, which cannot harden off so late in the season.
PROJECTS TO DO INDOORS IN FEBRUARY
Make a list of perennials that need to be divided once spring arrives. Fall-blooming plants generally respond best to division in the spring when the new growth is emerging. You’ll know a plant needs to be divided if:
- The flowers are smaller than they used to be
- A hole or dead space has developed in the center of the plant
- Plant growth is not as vigorous as it once was
- The plant has spread beyond its intended space in the garden
Get organized now for spring planting later. Make a list of plants you want to grow from seed and buy seed packets before the best selections are all gone. Inventory your seed-starting supplies to make sure you’ve got everything you need to start seeds indoors. Check to make sure your gardening tools are cleaned and ready for action.
Make a plan to improve your view – In the wintertime, we spend a lot of time looking at the view beyond our windows. Take a look at your view with a critical eye. Does it please you? If not, does it simply need a little editing or does it need a complete do-over? Do you like the plantings that are in place? Are there too many? Not enough? Not the right kind? Too overgrown? Too skimpy? Do you yearn to see a flowering tree in spring? A colorful shrub in autumn? Does the house need better illumination outdoors? Does the walkway need repair? Perhaps you visualize a trellis or other landscape feature. If you find your view lacking, make a list of what appeals about it and what doesn’t and then form a plan of action.
Create a Terrarium – A terrarium is basically an indoor garden in miniature. Terrariums fall in and out of favor and right now, they’re in favor. Whether you’re a slave to fads or not, a terrarium is a fun project to tackle while you’re waiting for spring. The University of Missouri Extension Publication G6520 provides good information on terrarium basics and includes a detailed list of plants suitable for terrariums and dish gardens (extension.missouri.edu/p/g6520 ). To get you started, here are a few terrarium fundamentals:
- Choose a clear glass, open-top container. It can be any glass container as long as it’s deep enough to accommodate plant roots. You can buy containers specially designed for terrariums, but look around your house to see if you already have something suitable. A vase, jar, goldfish bowl, aquarium, or even an old compote dish will work.
- Place a 1 to 2-inch layer of small pebbles in the bottom of the container for drainage. You can add some activated charcoal as well for further absorption.
- Add some damp potting soil.
- Carefully add a few small plants of various sizes and shapes. Tamp the soil firmly in place around the roots.
- Finish off the composition with a layer of pebbles or moss.
- Place the container where it will be warm but out of direct sun.
- Lightly water as the soil dries but don’t overwater.
Try growing an Air Plant (Tillandsia).
Tillandsias, better known as air plants, are popular right now but most people don’t fully understand their cultural requirements. First of all, they are epiphytes (plants that anchor themselves to other plants for physical support), which means they don’t grow in soil. So, yes, they do live on air, hence the common name. Therefore, you probably assume that because they don’t need soil, they also don’t need to be watered. And that’s where you would be wrong. Air plants evolved in the upper canopy of rain forests or in the cloud-covered Andes Mountains where they receive plenty of moisture from the air. But the dry air in your home is unlikely to provide enough humidity. So, mist them with clear water and notice how they turn from silver (dehydrated) to green (hydrated). Misting doesn’t provide enough hydration for air plants, however. About every 10 to 14 days, submerge the entire plant in tepid water for about 10 to 20 minutes. Then, place it upside down on a rack or towel to let the excess water drain away. Under watering an air plant is always better than over watering. You can tell the plant needs water if the leaves begin to develop a pronounced curve or if they turn brown on the tips. In addition to moisture, air plants need bright, indirect or filtered light. As for nutrients, use a water-soluble fertilizer developed for epiphytes and bromeliads. Add the fertilizer to the water before you submerge the plant.
Keep tabs on the health and well-being of your houseplants.
Inspect them for pests every time you water them. Common pests include white flies, scale, fungus gnats, spider mites, and mealy bugs. Treat as needed at the first sign of a problem. The University of Minnesota extension publication on Houseplant Insect Control offers sound advice on houseplant pests and includes photos of the most common ones. Clemson Cooperative Extension publication HGIC 2252 Common Houseplant Insects is another useful source for advice.
Assess your houseplants to see which ones would benefit from propagation. Over time, houseplants may grow too large for their containers, too heavy to be comfortably moved about, or just simply leggy and awkward looking. Rather than struggle to keep such a plant growing, a better idea is to start all over by propagating a new plant or plants. Houseplants may be propagated in many different ways. To name just a few:
- Offsets – Some plants, such as aloe, produce offsets that may be excised or gently broken away from the base of the mother plant and rooted.
- Plantlets – For plants that produce “babies,” such as spider plants, just snip off the baby and root it.
- Cane cuttings – The segmented stems of plants such as dieffenbachia may be cut into sections and rooted.
- Stem cuttings — Plants such as geranium or coleus have leaf nodes on their stems, from which new roots will grow.
- Leaf cuttings – African violet, begonia, Christmas cactus, and mother-in-law’s tongue are just a few of the many plants that can be started from leaf cuttings.
- Division – Roots of plants such as ferns and peace lilies may be separated into multiple plants and re-potted.
To learn more about plant propagation, see Virginia Cooperative Extension publication 426-002 on Propagation by Cuttings, Layering and Division. It provides excellent information on propagation methods in general. Also, Missouri Cooperative Extension publication G6560 on Home Propagation of Houseplants describes propagation methods for houseplants specifically. Many good books on propagation methods are available. One excellent choice is Plant Propagation, which was published by the American Horticultural Society in 1999. This reference book provides a wealth of “how to” information with accompanying photos and clear line drawings.