Skimmia is a beloved feature of winter, but upkeep is key to its good health, writes Peter Dowdall
Walking through a garden recently I couldn’t help but notice a shrub that should have been coming into its best simply wasn’t. Instead it was looking decidedly dejected. Looking sorry for itself, in human terms it was a bit like myself suffering from a bout of man flu. Like most men, I wouldn’t be one to grumble when feeling a little under the weather; no, much more like me to sit there and suffer in silence. Ahem, well, it is the male way.
The plant I am talking about was skimmia and, in particular, the variety ‘rubella’. Planted several years ago, this specimen was full of rich dark green leaves when it came from the garden centre, but after some time in a soil with a less than ideal pH, it is beginning to show signs of stress. The leaves are no longer that strong verdant colour, more yellow and wan now. The flower buds, too — such a feature of the winter and, dare I say it so early, Christmas time in the garden — should be visible on the tips of all the stems but they’re not. He’s certainly struggling. His poor health is shown up all the more by nearby skimmias which are thriving.
It’s not unusual to see a skimmia looking hungry, nor is it uncommon to see a random plant in trouble when neighbouring specimen seem to be fine.
There are two problems here. Firstly, the plant is lacking in iron, hence the yellowing of the leaves, and phosphorous and potassium are needed to promote flower buds.
Similar to camellias and rhododendrons, skimmias produce flower buds during this autumn for opening up during next spring. The buds of the aforementioned rubella are red and are as much a feature of the plant as the flowers, though when they do open up white, during next February and March, they will fill the air with the most delicious of aromas.
If the buds aren’t on the plant yet it’s unlikely that any action now will have an impact for this year. A generous feeding with a good Sulphate of Potash or Goulding’s Tomato Food a few times during July, August, and September will help to promote flower buds in future seasons. Indeed, I wouldn’t throw my hat or even my watering can at it for this year. It will certainly do no harm feeding it now — it may result in a few extra buds.
The yellowing of the leaves is just as straightforward to deal with, though a more ongoing approach is needed. The pH is obviously a bit too high, and thus any iron that is in the soil is trapped from the roots, so it will have to be given iron in a form that it can absorb. This means chelated or sequestered iron. Feeding a plant in this way will allow skimmias, rhododendrons, camellias, azaleas, and other ericaceous specimen to grow in alkaline conditions and soil with an otherwise incorrect pH.
I referred to rubella as a ‘he’ and that is because he is, in fact, a male form of the plant. Skimmias are largely dioecious, meaning that certain species produce male flowers while others will produce female. It is the female forms which will go on to produce the berries, provided that there is a male form nearby for pollination.
In recent years, many self-fertile forms have been cultivated which have both male and female flowers on the same plant. Rubella will produce the lovely red flower buds synonymous with Christmas — fragrant cloud is probably the best variety to produce buds which are whiter and, as the name suggests, extremely scented during the spring.
Of the self-fertile cultivars, reevsiana is a very low growing and extremely slow growing form which will never reach higher than 50cm in height. It is also very good for berries. Because it is so small, it is ideally suited to growing in a pot, container, or small rockery or Alpine garden.
The two varieties, temptation and obsession, will both produce relatively small clusters of white buds. Last year’s flowers will have turned into berries at the same time as the buds are produced and so the result is a medium-sized shrub which nearly always has some berries or flower and often both during the year.
For me, I couldn’t be without the skimmia rubella for the winter display but as for the one I saw recently, it will need a tonic and, like any good male, I’m sure it will continue to sit there calmly and with no fuss until the medicine takes hold and it’s back once more to its resplendent best.
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