Eucalyptus grow very well in containers, provided you stick to their rules! A version of this article was originally featured in the 2020 edition of ‘Ramblings of a Gumnut’.
Looking for a well-behaved standard eucalyptus for a container? Our 9 litre E. archeri standards are on sale until September 12 2022! Remember to pick them up along with an air-pot to keep their roots happy.
1. Choose the best Eucalyptus species
You can grow any Eucalyptus tree in a pot… after all, we do here! However, we have found that some species lend themselves to successful long-term pot cultivation over others.
Dwarf and medium sized species are the best candidates, as they tend not to race away. When trained, multistem specimens give excellent pots due to their stability and broader form.
E. gunnii ‘Azura’ is brilliant. Slower growing, compact in habit, with the classic small, round, blue leaves. Train it as a bush or a standard.
The amazing E. gunnii ‘Silverana’ is a new introduction. Very similar to Azura, with more silvery foliage.
E. pauciflora ssp. niphophila ‘Mount Bogong’ makes a terrific container subject; very interesting bark with winter interest. Standard niphophila is also an excellent candidate.
E. pauciflora ssp. pauciflora ‘Mount Buffalo’ is a very rare, beautiful dwarf snow-gum. Excellent white bark detail as it matures, and broader foliage than other snow-gums. Truly impressive when grown in a 30 litre pot or larger.
E. archeri and its cousin E. glaucescens are faster growing, but fantastic when trained as multistem specimens and pruned late May to keep them as compact, neat rounded bushes.
2. Select the right pot
All of our trees are grown in Air-pot containers. The Air-pot ‘air-prunes’ the roots, encouraging new roots to grow, which in turn keeps the foliage looking healthy. Traditional smooth-walled pots or grow-bags are bad news for Eucalyptus, especially if you intend to plant it out in the ground at a later date.
Should your tree require potting on, the basic rule is; increase the pot size by at least four times the volume. For example, a 3 litre airpot would go into a 12 or 20 litre airpot. The larger sizes are more flexible, and a 30 litre can go into a 100 litre.
Once re-potted, you can place your Euc inside a heavy ornamental container with drainage holes. Ornamental pots are both advisable and aesthetic; Eucs in metal or blue pots look particularly stunning.
Provided there is an air-gap of at least 30mm to allow airflow between the Air-pot and your ornamental container, root pruning should continue and your Euc will remain active.
Your snazzy container confers several properties on the system:
Helps prevent the tree from falling over in strong gales by adding weight at the base.
Reduces water evaporation and therefore stress to the tree.
Protects the roots from extreme weather.
Keeps the roots cooler in summer (black pots can get very hot).
Ensure your eucalyptus container (whatever the choice and style) is sat squarely over a solid flagstone, much larger in width than the pot base, to prevent any wayward roots from working their way into the ground. Moving the pot and breaking a sneaky tap-root can cause your tree some serious stress!
3. Compost is King
Tree compost needs to be stable, long-lasting, free draining, and moisture retentive. Cheap compost is a false economy for any plant.
To make your life easy in the long term and to keep your Euc happy, you can easily make your own blend using John Innes No. 1, Ericaceous compost, Swell-Gel, and low-nitrogen fertiliser granules. Alternatively, you could buy something bark-based and peat-free. See our website sundries page for our professional eucalyptus compost.
Apply a mulch of bark-chip to reduce water loss, or add slate or large pebbles to the top of the compost to weigh the pot down.
4. Siting your tree
Full sun and sheltered from biting easterly winds is best.
It can sit happily amongst other potted plants, provided it is not in shade or being overshadowed by a bigger tree or awning. If you’re going to use a very big pot or planter, then consider the placement carefully because moving it might be a labour intensive process!
Slow-release fertiliser granules will last your Euc for around 4 months from potting on. Thereafter, we recommend liquid feeding from April until the end of September with high-potassium Chempak No. 4 fertiliser every 10-14 days.
Every day from April till mid-October, even if it rains, and twice a week from mid-October until the end of March – check the soil first.
Water twice a day in summer if hot and windy. Shrivelled leaves never recover, and it won’t bounce back from dehydration like a bedding plant.
A simple drip irrigation system on a timer for about 8 minutes is absolutely the best thing ever, especially if you want to go on holiday!
Depending on how vigorous the species is, you may only have to prune once a year, on March 18th; National Eucalyptus Day in the UK.
An additional light trim of annual growth around the end of May is always good. Never prune during the winter. See our Pruning guidance page for more information on training and pruning.
Above: This is not the recommend pruning technique for eucalyptus trees.
8. Winter Protection
Any potted plant left outside during winter will be at risk when the temperature drops to 0°C, particularly for prolonged periods. The compost in the pot freezes, and root death occurs below -4°C.
Eucalyptus especially do not thrive under such conditions. Protect as you would any potted plant – see our guidance page for more details.
As always, if you have any questions you can just drop us an email and we’ll help you out!