Fivehorn Smotherweed (Hyssopifolia)

The Fivehorn Smotherweed (Hyssopifolia) is generally described as an annual forb/herb. This is not native to the U.S. (United States) and has its most active growth period in the summer . The greatest bloom is usually observed in the early summer, with fruit and seed production starting in the summer and continuing until summer. Leaves are not retained year to year. The Fivehorn Smotherweed (Hyssopifolia) has a short life span relative to most other plant species and a rapid growth rate.

The Fivehorn Smotherweed (Hyssopifolia) is not commonly available from nurseries, garden stores and other plant dealers and distributors. It can be propagated by seed. It has a moderate ability to spread through seed production and the seedlings have medium vigor. Note that cold stratification is not required for seed germination and the plant cannot survive exposure to temperatures below 52°F. has low tolerance to drought and restricted water conditions.

Plant Basics
Growth Rate Rapid
General Type Forb/herb
Growth Period Summer
Growth Duration Annual
Lifespan Short
Plant Nativity Introduced to U.S.
Commercial Availability No Known Source
Physical Characteristics
Bloom Period Early Summer
Displays Fall Colors No
Shape/Growth Form Single Stem
Drought Tolerance Low
Shade Tolerance Intolerant
Height When Mature 0.75
Vegetative Spread None
Flower Color Green
Flower Conspicuousness No
Fruit/Seed Abundance High
Fruit/Seed Seasonality Summer Summer
Seed Spread Rate Moderate
Gardening Characteristics
Propagations (Ways to Grow) Seed
Moisture Requirements Medium
Cold Stratification Required No
Minimum Temperature 52
Soil Depth for Roots 9
Toxic to Nearby Plants No
Toxic to Livestock No
After-Harvest Regrowth Rate Slow
After-Harvest Resprout Ability No
Responds to Coppicing No
Growth Requirements
pH Range 6.5–9.1 pH
Precipitation Range 7–7 inches/yr
Planting Density 0–0 indiv./acre
Soil Textures Fine, Medium
Soil Depth for Roots 9
Minimum Frost-Free Days 135 day(s)
Salinity Tolerance High
CaCO3 Tolerance High
Sustainability & Use
Leaf Retention No
Fire Resistant No
Causes Livestock Bloating None

Source: USDA, NRCS, PLANTS Database,
National Plant Data Center, Baton Rouge, LA 70874-4490 USA