Eucalyptus aggregata (Black Gum)

Gum trees (Eucalyptus) march to a different drum to every other tree. There are dozens of different species from all over Australia and we have distilled this list (there are probably 50 that would grow in Britain) into three. 1. Tall, broad, green and delicate leafed (this one). 2. Tall, straight, narrow and silvery/blue leafed (Eucalyptus glaucescens) and 3. Smaller, multistemmed, sparse with beautiful bark and blue foliage (Eucalyptus debeuzevillei). They are famous for the speed of their growth but this is ONLY the case if they have plenty of space and no competition when they're young and getting established. This, the Donald Trump of trees, when young, has enormous trouble competing with a bit of grass. Have you ever noticed how travelling by train is a great chance to see into thousands of back gardens? I've lost count of the number of thin miserable constipated Gum trees in back gardens between Horsham and London Victoria. The effect is instantly recognisable and is easily cured by removing all other plants within a metre of the trunk. This is true with all plants - but particularly so with Gums. The other non-conformist trait is that you can't grow it from cuttings - only seed. Normally, if we find a particularly fine example of any plant, we'd want to clone it - to produce lots more exactly the same. Occasionally this happens with Gum trees and the desire to clone it will be irresistible. We've tried and tried - even by micropropagation in our laboratory but to no avail. However, these come pretty true from seed and we always try to get seed from Australia that's been gathered on the same trees in a particular area. This helps. They're light sensitive and tend to grow away from other trees so the key is to either grow them on their own or surrounded by an equal amount of other trees in each direction. If possible. Sometimes they grow so fast that staking will not be enough - we've sometimes had to put guy wires up to support them for a few years. They'll stand up on their own eventually. All gums will grow by the sea but you've got to give them time. The salt wind will take the top out and it will eventually be low and wide and dense - just as if you'd been up on a ladder and kept giving it a haircut.

Eucalyptus aggregata responds well to being trimmed to a given height. Keep clipping the top and it will grow wide and low. A fine site but you'll have to do it 2 or three times each summer. We had one at the old nursery in Horsham, planted in 1992 and it was 80 ft tall and 50ft wide by 2014 when we had to have it removed. Some idiot had planted it right by the greenhouse. Me.

Drought resistance in plants (except in Cacti) is because the plant is so vigorous, it has the ability to find water where others may not. When first planted water like mad! It may need less water than others plants but it's also a vigorous and therefore a thirsty plant. And remember to water the rootball, not just the surrounding soil. In a windy coastal garden, plant small, stake well and the plant will grow a short, fat trunk with stocky growth rather than a long leggy one. Any other questions, phone us for advice.

N.B. When clipping several plants with the same tool, have a bucket containing a 5% bleach solution and swish your blades around for 30 seconds between plants to sterilise them. This will help avoid the chance of cross contamination of disease.

As with all woody plants, plant high, exposing as much of the taper at the base of the trunk as possible. Allowing soil to accumulate round the base of a tree can be fatal. Keep very well watered when first planted.