The Buddleja Garden

Neotropica Vol 81:

by Eliane Norman
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Buddlejas by
David D. Stuart
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Click images to enlarge

Buddleja glomerata

Posted 19th may 2017

B. glomerata is a plant I would not grow outside because it needs dryish condition. This presents a problem, as the plant can soon become potbound; then it flowers less and looks unhappy. The answer is to not just prune the top growth, but to trim the roots too. Last summer I knocked it out its 15 litre pot, took off any conjested roots and, returning it to the same pot, replaced about half the contents with fresh compost mixed with a little slow release fertiliser.

And this is the result the next spring - a happy plant covered in fuzzy flowers. It is trick I have used with a few a Buddlejas now. The alternative is to have all the tender Buddlejas in 100 litre pots, which is rather impractical in a tiny greenhouse.

Buddleja x wardii KR4881

Posted 9th may 2017

On the My Species page I took the bold step of applying my own identification and name to this plant, believing it to be a white-flowered form of B. alternifolia previously known as B. tsetangensis. I have waited a year to closely examine the flowers; although a healthy plant with very attractive foliage, it's extrememly parsimonious with its flowers when grown outside.

B.X wardii is considered a natural hybrid (or intermediate) of B. alternifolia and B. crispa; the original specimens were collected in Tsang-po valley (Tibet), a region where both species grow, and close to where the only known specimen of B. tsetangensis was collected.

Dissecting the flowers has convinced me KR4881 is not a hybrid of B. crispa, and hence is not B.X wardii. In the photo the ovaries of two Buddleja crispa types (plants of this species still frequently labelled as B. sterniana and B. agathosma) have been freed of the corolla and calyx, and are shown together with a dissected flower from KR4881. The difference in shape is striking, with the KR4881 ovary, style and stigma (gynúcium or female parts) being completely unlike either of the B. crispa examples. According to the literature, the female parts of B.X wardii should resemble those of B. crispa, with thick tomentum covering the upper half of the ovary and continuing onto the style. In KR4881 not only is the ovary shape and size very different, but the tomentum is sparse and restricted to the ovary; all its features are much more akin to those found in the flowers of B. alternifolia, and not intermediate between the two species. I also examined the flowers of "Longstock Gem", an artificial hybrid of B. alternifolia and B. crispa, and the gynúcium of this plant is almost identical to that of B. crispa.

I am pretty certain the plant should be labelled B. aff. alternifolia KR4881; B. tsetangensis has been reduced to a synonym of B. alternifolia and should no longer be used.

To return to the B crispa types, it is quite remarkable how different the two plants mentioned appear to be, with the leaves and corolla of B. agathosma four or more times the size of those of B. sterniana, yet the gynúcium scale and morphology are virtually identical, providing good evidence they should be included in the same species.

Buddleja sterniana

Posted 14th April 2017

Things are starting up in The Buddleja Garden at last. This past winter has been very mild indeed and has meant stalled flowers buds have survived. Many of the spring-flowering species and hybrids are beginning to open now, such as the Crispa Complex species B. agathosma and B. sterniana. Winter Sun, a hybrid of B. araucana has also flowered very well.

My B. sterniana was planted out a few years ago and didn't appear to do much at first. Orginally, I kept the plant in a pot where it stayed small and produced only a few weedy flowers. I was unsure whether it would prove hardy in a south-facing, but exposed, position. This year, however, it has finally exceeded my expectations; outside it has grown into a large straggly monster about 3 metres tall and 4 metres wide. The flowers, which appear before the leaves, cover the entire plant and from a distance it looks like a pale pink cloud. The plant is in for a shock - as soon as the flowers finish it is in for a rigorous pruning to tame its straggly character. It should regenerate into a denser, better shaped shrub by the autumn.

The 2017 Buddleja Diary is here!

Posted 8th April 2017

It's time to prune Buddleja davidii - I always prune summer-flowering species and hybrids in April. There is already a page on pruning, so I won't go into details. Remember - don't prune spring-flowering species until after they have flowered.

Watch out for those reverted, all green shoots on variegated cultivars such as Harlequin - like the one on the centre of the photo. Remove any branches now with reversions and keep a check once the growth restarts - the reverted shoots will be much more vigorous and could eventually take over the plant.

Buddleja forrestii - I have had some success with one B.forrestii planted in the garden, which has proved to be quite hardy. I have a second cultivar, one with massive leaves, already 30cm long, and brown tomentum. It's still in a pot and I've never seen the flowers - but it is growing well and I am making space for it so it can grow to what must be an impressive full-size. I have been warned this one might be a little less hardy, but I will take the risk as they never seem happy confined.

Buddleja Diary for 2017 coming soon!

In the meantime, here are a few antique prints to enjoy; click to enlarge.

Buddleja colvilei

B. alternifolia

Buddleja alternifolia
Buddleja x intermedia

B. intermedia

B. japonica

Buddleja japonica
Buddleja sessiliflora (as Buddleja verticillata)

B. sessiliflora

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