Eucalyptus subcrenulata – Tasmanian Alpine Yellow Gum – 1 of our wonderful Swamp Gums

Eucalyptus subcrenulata – Tasmanian Alpine Yellow Gum

How to use in the landscape and/or garden:  How to grow or train it to get the best out of it

Fabulous Specimen Tree for the wider landscape, arboretum collection or avenue planting and for the smaller, medium and larger garden:

Growing a full-sized standard: planting the tree and running away is an option, but it won’t necessarily give you the best results.  We suggest you maintain a leading shoot and tip prune the lateral shoots to encourage bushiness.  Keep all the sides shoots as they are building up the strength of the main trunk.

• To grow a large specimen, leave the tree to grow up naturally thereafter.
• For a small tree, tip prune the leader when it reaches 1.2m, thereafter let the head develop. Then prune the tree every March 18^th and end of May to keep your tree small and bushy.

For more, see our guidance notes for growing specimen Eucalyptus in our Help and Advice section.

For monthly emails on how and when to prune and care for your Eucalyptus, sign up to our Gumnut Club and we’ll send you the Bush Telegraph – it’s totally free and you can unsubscribe at any time.

Growing ‘shrub-on-a-stick’ clipped standard: this is an opportunity to grow a Eucalyptus in a confined space and control its overall size. You can produce a small tree on a trunk with a height of anywhere between 2.4m (8ft) and 4m (12ft).  Prune back growth every March 18^th or thereabouts and tip prune the annual growth back by up to 90% at the end of May. Light tip pruning can be done again during July, but no later. Don’t prune from August through to February.

Growing a multi-stemmed bush or tree.  E subcrenulata responds well to coppicing, once it has attained a trunk of some 125 mm in diameter and readily produces a multi-stemmed specimen

Why would you want to do this?

To create:

• a tree with more body or ‘mass’ of branches and foliage for screening purposes. Once grown back up to its full potential, it will now have several main trunks
• an attractive multi-stemmed architectural tree, especially if it has exceptional bark
• to control height, whereby your Euc can be usefully maintained anywhere between 2.4m (8ft) and 7m (20ft), but genetically it will want to grow taller if ignored.

REMEMBER: No grass, no weeds and a thick boring bark chip mulch, to a depth of 150 mm (6 inches) are essential to assist with good establishment. Our research trials have demonstrated that grass around the trunk of Eucalyptus prevent the trees from quickly establishing and can completely stop them from growing.

Pot Culture outdoors:  E. subcrenulata can be successfully grown as a multi-stemmed shrub in a container provided you are prepared to pot on at the recommended intervals and to supply it with sufficient water and food during the growing season.

Always keep pot grown Eucalyptus in the air-pot container system for healthy and happy trees.

For information on how to successfully grow Eucs in pots, visit our Blog entitled ‘How to grow a Eucalyptus in a pot and keep it alive!’

Hedge-Screens & Windbreaks:  E subcrenulata  is an excellent choice for a hedge-screen as it readily produces sub-lateral shoots and retains its lower branches for much longer than other Eucs. – i.e. keeps the branches sprouting off the side-branches and finds no problem in becoming bushy.  This is unusual for most Eucs and makes E subcrenulata  a great subject for a bushy billowy hedge screen.

Always prune your hedge-screen March 18^th and maintain a profile like a capital ‘A’.  That is broad bottom, narrow shoulders and a flat head.  This allows light to all parts of the hedge and keeps it bushy.  If you let your hedge develop into the shape of a capital ‘V’, its bottom will open up…not a great look!

Floral Art:  E subcrenulata produces excellent cut foliage for Flower Farmers and floral art. Very useful where fragrant, green foliage is required. Very popular for Christmas wreaths and garlands.

Firewood Production:  E subcrenulata is great for growing biomass and firewood logs, especially on wet clay soils.

Do give us a call on our nursery mobile 07307 413 052 if you would like to discuss growing firewood with one of our consultants

Rural/Agricultural:

– Good shade tree for livestock to stand under.   Eucalyptus provide a cool environment for horses, cattle, llamas, sheep to shelter from the sun on hot days, as the mass evaporation of water through the leaves creates a cool shady canopy beneath. Good choice for silvopasture.

– Green foliaged species, which looks for comfortable and not ‘foreign’ in a rural setting – reminiscent of Willow Trees

Ecology:

– Bees. All Eucalyptus produce flowers with nectar and pollen, but this species has prolific flowers making it a real draw for honey bees and other pollinators in late summer when forage is scarce

– Habitat creation and Game Cover:  this species lends itself to providing good trouble-free habitat creation for wildlife and game cover, when planted in groups. At the nursery, the Goldfinches enjoys nesting in our subcrenulata hedge.

Birds enjoy roosting in Eucalyptus trees and Pheasants like rootling around underneath them.

– Chickens: The shredded foliage of E subcrenulata  is excellent at keeping Chicken nest boxes and hen houses free of red mites, which detest the presence of Eucalyptol. I used to line our Chicken boxes with shredded leaves, strew the floor and pile up the spindly branches for the chickens to make nests.  It was all great till the foxes moved into the next field L

Environmental:

– Growing on the Coast:  E subcrenulata is tolerant of cold exposed conditions and salt laden winds, once mature in the ground. Newly planted trees may require a wind break shelter using something like horticultural fleece or sail cloth, for their first winter in the ground with you.

There is a successful plantation of E subcrenulata in sight of the sea at Wadebridge in Cornwall

– Drying up intermittently wet soils. Hailing from damp hillsides in Tasmania and soggy valley bottoms in the wild, E subcrenulata does prefer a moisture retentive soil and does well at drying up a wet UK soil.

Dry up wet ground that intermittently floods, gain remedial treatment for winter boggy ground or soil which suffers from unwanted ponding.  If you have un-usable winter-marshy pasture,  our research has shown that installing a small plantation of swamp gums will help dry up an area of ground over a period of time and give you a crop of firewood logs too, if coppiced every few years; certainly worth giving it a try.  Just bear in mind that these trees are not ‘aquatic’ and will do best if the ground drains somewhat for part of the year.  Furthermore, coppicing would need to occur in rotation, so that you didn’t lose all of the trees and therefore the pumping of water in one go.

– Sustainable Drainage Systems aka SUDS: an 18m row of E. subcrenulata has been successfully used at one end of our nursery to absorb the overflow water from our irrigation system.  Planted at 1.5m spacing, around 2014, the trees are pollarded down to around 2m every 2-3 years and allowed to grow up to around  6m (15-20 feet) in between. The water used to pond around their ankles every winter, but the ground around them is now dry and passable even after prolonged, heavy rain.  They have retained their foliage down to almost ground level and now form a robust hedge screen for the nursery.

E. subcrenulata will draw on drain water percolating into swales or similar. Coppice or pollard every few years if you need to control the overall height of the trees. Eucalyptus draw on ground water for twelve months of the year, unlike willows, which lie dormant for 5 months through the winter.

– Tolerant of cold and exposed growing environments inland: E. subcrenulata will grow in open fields and pasture, once established.  Newly planted trees may require a wind break shelter made from horticultural fleece or sail cloth, for their first winter in the ground with you; this very much depends on the level of exposure.

For quick and efficient establishment, follow our detailed planting instructions.

No grass, no weeds and a thick bark chip mulch, to a depth of 150 mm (6 inches) are essential to assist with good establishment.