Chrysanthemum multicaule Seeds | Annual Chrysanthemum
LATIN NAME: Chrysanthemum multicaule
COMMON NAME: Annual Chrysanthemum
Plant Profile
Chrysanthemum multicaule is a small North African annual that has spent most of its cultivated life under a name it no longer owns. It is now placed in Coleostephus, a genus of two or three species separated from the great chrysanthemum complex, but the seed trade has not caught up and probably never will.
The plant makes a bushy mound of deeply cut, slightly fleshy leaves and covers itself in yellow daisies for months, each one with a ring of broad ray florets around a darker disc. It ranks among the cheapest and fastest annuals in the trade, and it flowers in eight weeks from sowing.
It comes from Algeria, from the stony hills and coastal slopes of the Tell, where the winter is wet and the summer is dry and hot. Desfontaines described it in the late eighteenth century in his Flora Atlantica, the great North African flora that he compiled from the mountains around Algiers. The epithet means many-stemmed, and a well-grown plant is exactly that.
The history of its genus is a lesson in how names lag behind evidence. The old Chrysanthemum held everything with a daisy head and a chrysanthemum look; molecular work found that the group was a pile of unrelated lineages, and the annual Mediterranean species were moved out into Coleostephus, Ismelia, Glebionis and Mauranthemum. The same family turns up again in Chrysanthemum indicum, Chrysanthemum paludosum and Ageratum houstonianum.
Science & Biotechnology
The daisy head is two flowers in one. The ray florets are sterile or female and carry the show, and the disc florets in the centre are bisexual and make the seed. The whole structure is a compressed inflorescence, and the ray florets are the outermost florets of that spike, flattened and enlarged.
The fruit is an achene with no pappus, which is unusual in the family and useful in the garden: the seed falls close to the parent and the plant naturalises in gravel and at path edges without travelling far. Each head makes a few dozen seed, and a single plant can produce several thousand in a season.
Like many annuals of Mediterranean climates it is a winter grower in the wild, germinating with the autumn rains and flowering before the summer drought. In cultivation that rhythm can be reversed or ignored, and the plant will flower at almost any season if it is sown at the right temperature and given enough light.
Uses & Benefits
It is a bedding annual, pure and simple: for edging, for filling gaps, for a low mound of yellow at the front of a border or in a container. It is not a plant with a history of medicine or craft, and its only economic role is the seed packet and the tray of seedlings at the market.
The yellow is a clean, strong, slightly greenish yellow that mixes badly with pink and well with blue, and the double forms sold as Gold Plate types are denser and more formal than the single. Both are useful, and both look better in quantity than as isolated specimens.
It is also a useful cut flower for small arrangements, though the stems are short and the vase life is a week at best. In a mixed annual border it earns its place by flowering when the spring sowings are still small and the summer perennials are not yet open.
Growing from Seed
Sow under cover in early spring at about eighteen degrees, on the surface and barely covered, and germination takes a week to ten days. Prick out early, because the seedlings resent root disturbance once they are established, and plant out after the last frost.
It wants full sun and ordinary, well-drained soil, and it resents rich feeding, which produces leaf at the expense of flower. Water until it is established and then leave it; in a dry summer it will flower longer than in a wet one, and it will not need staking.
Deadhead to keep it going, and it will flower from June until the first hard frost. If you want it to come back, leave a few heads to ripen and shake them where you want the seedlings; in a gravel garden it will make itself at home and return for years.
Our Take
This is not a plant that anyone writes poetry about, and it does not need to be. It is a working annual: cheap, fast, reliable, and generous with colour at a time of year when the garden can look thin. There is a lot to be said for that, and very little that needs saying.
Grow it in a mass, in full sun, in soil you would not waste on something more expensive, and it will do exactly what an annual is supposed to do. The taxonomy is a footnote; the yellow is the point.
Related Reading
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