Epimedium brevicornum Seeds | Short-horned Epimedium
LATIN NAME: Epimedium brevicornum
COMMON NAME: Short-horned Epimedium
Plant Profile
The label tells you where to look. Barrenwort flowers carry four small inner sepals and four petals drawn out into hollow spurs, the nectar tubes that project backwards out of the flower. In this species those spurs are short, and that is the whole basis of the epithet. The flowers hang in loose sprays above the foliage in spring, and the plant beneath them is a spreading mat of thin rhizomes carrying leaves divided into three, each division divided again, with a spine-toothed edge.
Inside that complex, leaflet shape, spur length and the number of divisions are the working characters, and garden plants have been renamed repeatedly as the taxonomy shifted. Flower size and the proportion of the spur remain the most reliable field marks.
These are woodland plants with a rhizomatous habit: a network of slender underground stems creeps through leaf litter and sends up foliage on wiry petioles. The leaf is biternate to triternate, a compound of compounds, and the leaflets in this group are heart-shaped at the base with a spiny margin. New growth flushes bronze or pink before it hardens to green, and in mild climates the old leaves persist through winter, which is what makes the genus useful as cover under trees.
Science & Biotechnology
The chemistry is why this genus has a research literature far larger than its garden footprint. The marker compound is icariin, a prenylated flavonol glycoside built on kaempferol with a rhamnose sugar and a prenyl group attached; alongside it sit the epimedins and a series of minor glycosides. When the material is metabolised, icariin is converted toward icariside I and then to icariside II, also called baohuoside I, with the sugar stripped away and the prenyl group left intact. Icaritin is the aglycone at the end of that chain, and standardised extracts are sold on icariin content for exactly this reason.
Documented pharmacology runs in two directions. The first follows the flavonoid’s resemblance to the phosphodiesterase-5 inhibitors, with icariin studied in vitro as an inhibitor of the PDE5 enzyme. The second is bone biology: extracts and pure icariin have been examined for their effect on the balance between osteoblasts and osteoclasts, which is the rationale behind the traditional use of the leaf in formulas for weak bones. The aglycone icaritin has been carried into clinical development as a candidate anticancer compound. None of that makes the plant self-medicating material, and the confusion in the botanical trade is a good reason to treat unlabelled dried leaf with caution.
Uses & Benefits
Barrenworts vary across their range and cross readily, and the genus has been a headache for taxonomists since the horticultural monograph that sorted it out in the 1930s. Chinese medicinal material has been traded under several names within the same group, and Epimedium macranthum, once applied to cultivated plants of this affinity, is now understood as part of the E. grandiflorum complex rather than as a clean species.
Dried leaf is the traded part. Cut the aerial growth in the warm part of the year, dry it in shade so the colour holds, and store it whole rather than powdered, because the flavonoids keep better in coarse material. In the garden, the same leaf makes an undemanding evergreen carpet once the rhizomes have run.
Growing from Seed
Barrenwort seed carries a small fleshy appendage, an elaiosome, that ants find irresistible. They carry the seed underground to the food body and abandon the rest, which is how these plants travel through a wood. For the grower it means the seed you collect is fresh and short-lived: sow it as soon as it is shed, in a shaded frame, and keep the surface moist.
Use a mix of leaf mould, composted bark and a little grit over any soil that drains, and set the plants thirty centimetres apart; they close the gap within a couple of seasons. Water through the first summer, then only in drought, since the rhizomes carry the plant through dry spells. Divide the clumps in early spring, just as new growth breaks, and replant the divisions with the rhizome barely covered.
Our Take
Barrenworts answer the hardest spot in a garden, the dry shade under a tree, and this one earns its place on the spring flowers alone. To build a collection, large-flowered barrenwort carries the biggest blooms and arrow-leaved barrenwort is the other classic medicinal species. Chinese barrenwort is the name most often seen in the herb trade, and mayapple is a good woodland companion with the same taste for leaf litter.
Related Reading
Gardeners who grow Short-horned Epimedium often pair it with these related subjects: