Silverheels horehound
Marrubium rotundifolium
Silverheels horehound (Marrubium rotundifolium) is a groundcover suited to the Colorado Front Range. It matures to about 6–12 in tall and 18–24 in wide, needs low water, and prefers full sun. Silver-white round leaves form a velvet mat; pollinator-friendly white flower whorls.
Plant Select®low water6–12 in tall and 18–24 in wideXeric / water-wiseZones 1–3 (can be planted near the house)Deer-resistant
Photos
- Photo 1: Stan Shebs, Wikimedia Commons (CC-BY-SA)
- Photo 2: Krzysztof Ziarnek, Kenraiz, Wikimedia Commons (CC-BY-SA)
At a glance
Will it survive here?
- Hardiness zones
- USDA 4–8
- Water needs
- low water
- Sun
- Best in full sun.
- Soil
- loam, sandy, well drained only
- Soil pH
- 6.5–8.0
- Hail tolerance
- high
- Wind tolerance
- high
- Salt tolerance
- moderate
- Firewise (defensible space)
- Zones 1–3 (can be planted near the house)
- Site uses
- Hot south- or west-facing walls, Hellstrips / parking strips, Slopes & erosion control
How big, what shape?
- Mature size
- 6–12 in tall and 18–24 in wide
- Growth habit
- Mat-forming
- Planting spacing
- ~17–24 in apart
What it looks like, and when
- Bloom time
- mid summer
- Bloom color
- white
- Bloom length
- 2–3 weeks
- Foliage
- Evergreen
What it will do to your yard
- Foot traffic
- No foot traffic
Who else benefits
- Pollinator value
- low
- Deer
- Generally deer-resistant
- Colorado native
- No
Using Silverheels horehound as a groundcover
Silverheels horehound forms a low mat. It fills in densely, crowding out most weeds. On a slope it helps knit the soil together and control erosion.
Planting & establishment
Sharp drainage essential; rots in wet sites.
Frequently asked questions
- Is Silverheels horehound good for the Colorado Front Range?
- Yes, Silverheels horehound is a well-suited groundcover for Colorado's Front Range.
- How big does Silverheels horehound get?
- It matures to about 6–12 in tall and 18–24 in wide.
- How far apart do I plant Silverheels horehound?
- Space Silverheels horehound about 17 in apart for a faster, fuller cover, or up to 24 in apart for a looser planting.
- Is Silverheels horehound hardy on the Front Range?
- Silverheels horehound is hardy in USDA 4–8. The Colorado Front Range spans roughly USDA 4b–6a, so it is well within range.
- How much water does Silverheels horehound need?
- It needs low water once established.
- Is Silverheels horehound native to Colorado?
- No. It is not a Colorado native, but it grows well on the Front Range.
- Is Silverheels horehound deer-resistant?
- Silverheels horehound is generally considered deer-resistant, though no plant is deer-proof when browse pressure is high.
- Is Silverheels horehound a good firewise plant near the house?
- Silverheels horehound is a lower-fuel choice suitable in defensible-space zones 1–3, it can be planted near the house when kept well irrigated and maintained. This is general suitability guidance based on CSU Extension firewise plant lists, not a guarantee that any plant won't burn, a well-irrigated, well-maintained plant is the goal. Follow CSU Extension defensible-space guidance and check with your local fire district before planting in the wildland-urban interface.
- Can you walk on Silverheels horehound?
- Silverheels horehound isn't meant for foot traffic, site it where you won't need to walk across it.
- Will Silverheels horehound spread or stay put?
- Silverheels horehound is mat-forming. Give it room to fill in and edit the edges to keep it where you want it.
- Is Silverheels horehound good for a slope?
- Yes. Silverheels horehound helps hold soil on Front Range slopes and control erosion once its roots knit in.
- How long does Silverheels horehound bloom?
- Silverheels horehound blooms for about two to three weeks on the Front Range. Bloom timing shifts a week or two with elevation and spring weather.