The plant commonly identified as lamb’s ear (Stachys byzantina) can be a controversial choice for your garden. This native of Turkey is treasured for it silver, gray wooly foliage and tall stalks of pink-purple blooms. The reason for the controversy is its ability to spread by seed, perhaps a bit more vigorously than your neighbors might appreciate. As a result it can be borderline invasive.
Aggressive reseeders can be a blessing or a curse; it just depends on whether you want lots more of them, and how much space you can give them to grow.
When a plant that you would like to grow is a bit too aggressive in its growth habit, it might be helpful to look at some of the cultivars available for that plant. Cultivars are plants that are selectively bred to retain desirable characteristics, while minimizing undesirable traits of the plant. They are the same genus and species, but have slight differences in terms of performance in the garden. Most often the cultivars are propagated by asexual means like division, root and stem cuttings, offsets, grafting and tissue culture. These means of reproduction guarantee that the plants produced are genetically identical to the parent plants.
Lamb’s ear is a great example. If you want the fuzzy foliage, drought tolerance and deer and rabbit resistance of S. byzantina, but don’t want the aggressive reseeding behavior, there are several great sterile cultivars available.
Silver Carpet (S. byzantina ‘Silver Carpet’) is a personal favorite of mine. It is a nonblooming species that tolerates both sun and shade, is drought tolerant, forms a dense mat of low growing silver fuzzy foliage and spreads only by the clump size increasing, no seeds or runners to invade other parts of the garden. They can be vigorous, so give them some space to expand.
If you want a showier lamb’s ear, ’Helen Von Stein’ (S. byzantina ‘Helen Von Stein’) might be your choice. It forms a taller more upright form of the desirable foliage. It blooms occasionally, and if you want to prevent reseeding then dead-head this cultivar before seed formation. It will be easier than it is for the aggressively blooming S. byzantina. It shares the drought, deer and rabbit resistance with other Stachys, but it does prefer full sun.
Cultivars can be a useful alternative for plant selection. Understanding what traits they bring to a garden, and perhaps more importantly what they don’t bring, is useful information. While minimizing blooms and seed production makes these plants less valuable to pollinators and birds, sometimes the trade-off might be useful for specific conditions. Just make sure you include lots of other blooming plants in your garden plan.
Submit gardening questions to csumg2@elpasoco.com or call 719-520-7684. The in-person help desk is open 9 a.m.-noon and 1-4 p.m. Mondays, Wednesdays and Thursdays. Visit elpaso.extension.colostate.edu and register for upcoming classes at epcextension.eventbrite.com.