Ever since I posted about this unusual Bidens almost exactly a year ago, I have noticed that it keeps showing up in the ‘top posts & pages’ so readers are obviously interested in it and how it performs. I thought it was late to flower last year because I had grown it from seed in March and it was going to need several months to attain it’s height and maturity. When it did flower it was stunning in it’s simplicity. Dainty and delicate white tipped canary yellow flowers on tall wiry stems. Frankly, when it died away last winter I didn’t expect it to re-appear, and so I was delighted when it did. Bidens is not generally considered to be hardy but this variety is reckoned to be hardier than most.
Bidens aurea 21 May
It was probably due to the very cold and wet spring this year but it took forever to appear and it was the end of May before I noticed any new growth. However, I was delighted to see far more growth than just the three plants from 2012. It had spread several feet and now covered an area 1 metre across. This fresh young growth sat reluctantly through spring and didn’t do very much until the end of July when it suddenly took off and the first flowers finally appeared at the end of August, exactly the same as last year!
If anything, I think it might be slightly shorter this year which may be due to the horrible clay soil it sits in and the corresponding lack of nutrients but the foliage colour is a good dark green and it looks very healthy. The flowers, three or four at the top of each stem, open successively and seem to last a week or so before the next bud opens.
If it spreads again next year I may have to re-classify it as invasive because, as much as I like it, I don’t want it to take over the border. It is already swamping a few things so a bit of division is called for next year. A number of visitors from our horticultural society have asked for a piece so it will end up in several more gardens.
A plant I can heartily recommend. If only it was scented!
This variety of the popular north american Bidens aurea was introduced many years ago by Hannay’s Nursery in Bath and is one of the hardier forms which is why I decided to try it here in the chilly Cotswolds. The seed, which is barbed helping it to hitch a ride from grazing animals, came from last year’s Cottage Garden Seed Exchange and was easy to germinate into very sturdy little plants. However, during April, May and June they just sat there at about 30cm tall waiting for some warmth and sunshine.
I had read that this form of Bidens can run and become a bit of a thug if it likes your soil and aspect so I decided to plant it carefully in several very different parts of the garden. To my total surprise, it has done best with it’s feet in sticky clay and is now 120cm high and still growing. The flowers are a lovely lemon yellow tipped with white, similar in size and shape to Coreopsis to which it is closely related.
The dark green foliage and wiry green stems makes me wonder why this daisy species is an ‘aurea’ which usually means ‘golden’ or ‘yellow’ foliage. Perhaps it refers to the yellow flowers although this would be a departure from the usual nomenclature rules.
Received wisdom suggests this variety should be treated like a Penstemon, often hardy enough but take cuttings just in case. Also, don’t cut the old foliage down until April to give some protection over winter. I am going to collect my own seed and grow a few new plants each year given how easy they are to propagate.
The tall airy stems are strong and upright and do not require staking, a definite bonus in my windy front garden, and the flowers seem to last for ages attracting bees and other pollinating insects. Overall, a very garden-worthy plant for late summer colour which blends in well with reds, purples, yellows and whites and doesn’t mask the plants behind it. I have it planted in front of my Photinia hedge with white and dark purple Cosmos, Agastache and Nicotiana alata and alongside permanent shrubs of Euonymus japonicus and Amelanchier lamarckii. It just seems to work.