Garden Q&A - Battling invasive plants
Q. I know I have a few invasive plants. Can you mention the most common ones and the more natural replacements?
Robin from Lake Milton
A. Yes, we can. So glad you are taking a step forward in addressing invasive species. We need to take care of our environment by eliminating invasive plants from our gardens – where some of them originated. Nonnative plants can take over natural habitats that animal and insect communities often rely on to exist.
If you have invasive plants in your garden, and they don’t seem to be a problem, that is not a good way to think about it.
Many times the birds take their seeds and the problem elsewhere – into the woods and under the electric lines along our roads. The wind and birds can spread seeds great distances where they can get a foothold and out-compete native plants.
Here are four common invasive plants that might be in your landscape. Consider replacing these with an alternative that will perform the same role but not take over your landscape:
Barberry (Berberis thunbergii). It is a low-growing, multistemmed deciduous shrub with a single thorn at the base of each leaf with small yellow flowers in spring, followed by red berries from summer through winter. Pull seedlings and dig out mature plants or apply herbicide to cut stumps. A great alternative is the Dwarf Fothergilla (Fothergilla gardenia). This is a native shrub that has bottlebrush-like white aromatic flowers in spring before leaves appear.
Purple Loosestrife (Lythrum salicaria). The 2- to 4-foot-tall spikes of purple flowers can be found in wet areas where they choke out native vegetation and destroy wildlife habitat. This is a tough one to get under control. Cut flower spikes to prevent seed production. Digging can be effective, but it will re-sprout from roots left in the ground. Apply an herbicide labeled for use on rights of way and near water as a last resort. Instead plant Fireweed (Chamerion angustifolium) a native perennial with red woody stems and willowlike leaves topped with pink to purple flowers in summer, growing 2 to 5 feet tall.
Multiflora Rose (Rosa multiflora). This is the only rose bush that will come up without you planting it. This thorny, thicket-forming shrub can grow 15 feet with small flowers with small red hips in fall. A single multiflora rose can produce up to a million seeds in one year to be spread by birds. Cutting or mowing during growing season (three to six times) for two to four years can help. You can also apply herbicide to foliage in the summer. Instead, plant Prairie Rose (Rosa setigera), a native rose shrub with deep pink flowers growing 6 to 12 inches tall.
Asian Bush Honeysuckle (Lonicera morrowii, L. maackii and L. tatarica). This sweet-smelling, upright shrub from 6 to 15 inches tall with green leaves and tubular fragrant flowers in spring. It can outcompete and shade out native woodland species. Grow this instead, Bush Honeysuckle (Diervilla lonicera), a native shrub with tube-like flowers in late spring and early summer with yellow-orange foliage in fall. It grows 2 to 3 feet tall.
Discover more about invasive plants and their replacements at http://go.osu.edu/invasives
Pam Baytos is an OSU Extension master gardener volunteer in Mahoning County. The clinic is now open for spring. Call 330-533-5538 to submit your questions. Regular clinic hours are 9 a.m. to noon Mondays and Thursdays.