Growing euphorbia’s successfully:  Getting more of them; multiplication

Rikus van Veldhuisen

Growing euphorbias successfully – Multiplication: Getting more of them. Euphorbia World 10(1)2014, page 26 – 27.

Recently there was a discussion on Planet Euphorbia (Facebook) dealing with Euphorbia lavasoa. Formally there is no Euphorbia lavasoa known and the plant meant here was in fact Euphorbia species ‘Lavasoa’. In this case ‘Lavasoa’ is an hotel in the vicinity of Fort Dauphin, Madagascar and our plant of the relationship Euphorbia hedytioides is supposed to grow in the shrubs behind the hotel. Having cleared this fact some readers replied with the question if any cuttings were available. Growing euphorbia’s successfully is all about multiplication. If not only for keeping certain species in cultivation, but merely because of one of the most rewarding satisfactions of our hobby is to pass on nice plants to anyone who values them.

Euphorbia species ‘Lavasoa’.

Euphorbia species ‘Lavasoa’ makes a small bush growing from a very thick rootstock (see figure 1).  The most characteristic feature of this plant may well be the waxy shiny bright green leaves. The primary branch bears at first alternating leaves, contrary to the secondary branches, which are relatively thin and bear the leaves at a thicker end, where also the next generation of side-branches are born. This manner of branching is very typical for this related group of species.

Euphorbia species ‘Lavasoa’ can be propagated easily from cuttings, but when such a lateral branch is rooted it grows at first in a untidy low spreading bush and shows little resemblance with a plant grown from seed, because the seedlings form a erect high growing central stem first (see figure 2).

The flowers of Euphorbia species ‘Lavasoa’ are minute (see figure 3). I had grown this plant for many years and believed it was unisexual and being a male. A friend of mine received a cutting years ago and when visiting his collection I noticed with pleasure it had grown into a nice specimen. I was amazed by him commenting he had grown 4 seedlings of it. On a closer inspection of his plant there were indeed also female flowers. When home again I took my plant out a corner of my collection and put it in a place I could easily pay much more attention to it. It didn’t take long before I also found some female flowers, which were controlled pollinated with its own pollen. It took quite a bit of an effort to get two fruits the first year, containing 4 seeds and the next year only one fruit with 2 seeds. Only of this last two seeds one germinated, which yielded the seedling pictured in figure 2. This easy to propagate plant by cuttings wasn’t at all too easy to propagate by seeds.

Getting things done the easy way.

In the process of getting more attention as time passed by, I also repotted Euphorbia species ‘Lavasoa’. Several thick swollen roots were attached to the main stem with thinner necks, which is the case for quite a few species of euphorbia. It was relatively easy to cut off such a thick root and to pot it up. Within a few weeks the root threw out several new branches, which all had the features of a central stem (see figure 4). This still wasn’t my goal as a seedling has just one central stem. All stems were cut off except one and immediately potted in moist peaty compost without any clay. Nearly all Madagascan euphorbia’s hate clay in the potting mix, as I found out the hard way many years ago. In a matter of months I have 6 nice plants of Euphorbia species ‘Lavasoa’ all growing in the original seedling way (see figure 5). Perhaps unnecessary to say a lot of succulent euphorbia’s with thick tuberous rootstocks can be propagated in this way.

Figure 1

An older plant of Euphorbia species ‘Lavasoa’, received as a cutting 6 years ago and has proved to be a vigorous and easy grower on a warm slightly shaded place.

Figure 2

A 30 centimeter high, one year old seedling of Euphorbia species ‘Lavasoa’ showing the initial growth of a central stem before branching.

Figure 3

The minute male flower of Euphorbia species ‘Lavasoa’ surrounded by the waxy shiny bright green leaves.

Figure 4

The rootstock has thrown out 6 ‘central’ stems, but isn’t still not looking like an original seedling.

Figure 5

The same plant as in figure 4 but after some serious pruning and is now looking much more like a seed grown plant.