Xanthorrhoea species (Grass Trees)
Xanthorrhoea priessii is a Western Australian species. This species was one of the plants used by the winning garden at the Chelsea Flower Show. Xanthorrhoea quadrangulata and Xanthorrhoea semiplana are the South Australian species of Grass Tree.
At an Arboretum near here, Xanthorrhoea preissii and Xanthorrhoea semiplana have both been planted on deep sand. After four years of growth in the ground, the cluster of leaves is about 60cm tall and beginning to ‘vase’ out in a very graceful way. The width of the clump is larger than the reach of two hands joined finger tip to finger tip as if holding a large bunch of flowers.
It is certainly worth while growing these for the leaf display if this is what the growth is like after 4 years. Xanthorrhoea preissii does not make a trunk, whereas the other does. However to see a ‘decent’ trunk on Xanthorrhoea semiplana in one’s lifetime is probably only to be dreamed about!
Xanthorrhoea need a sunny well drained position. They look wonderful growing in a rockery and will also look great in a large pot as an impressive feature plant. Specimens have flowered after 7 years in Brisbane and 10 years at the Australian National Botanic Gardens.
It has been discovered that the Yellow Tailed Black Cockatoos love the seed pods that form along the flower stem which can be as much as 4-5 metres tall. They have been observed eating them soon after sunrise between Tintinara and Keith on the side of the road.
Blog Entries
June 30th, 2006 at 9:45 pm
[…] Xanthorrhoea species (Grass Tree) from Kalbarri WA .Photo by Jeff A friend, Jeff, emailed this photo to me wondering about the botanical name (which he found for himself before I had read his email.) He said the photo was taken at Kalbarri in WA so I thought it probably was specifically Xanthorrhoea priessii when I looked up a reference. Then I realised that I had called the trunkless species by this name in a previous post. […]
October 15th, 2006 at 7:13 pm
CAn you please give me some feedback to help me with a successful transplantation of semi mature grass trees. What will help them survive?
I would be really greatful of some advice to keep them alive. They look great, what will help me keep them going?
Do I need to cut them back?
October 15th, 2006 at 10:15 pm
[…] After the grasses seminar we went to Cromer Conservation Park for a picnic lunch. Husband had been bird watching there and was distracted by the great display of wildflowers. There were a number of these Xanthorrhoea plants in flower. They were growing on deep very well drained sand. […]
October 16th, 2006 at 7:46 am
Every plant that I have seen ready for transplanting has had the leaves trimmed to around 30cm or less, I assume to reduce transpiration stress.
They do not have an extensive root system. They need good drainage, so raise the planting spot if needed, and give it an open sunny aspect. Keep moist but not soggy, so test the soil in the top 4-5cm for dryness before watering again. I think a mulch of small gravel or course sand, failing that, leaf litter to retain moisture during the summer and keep soil temperature from extremes while the plant is establishing is a good idea.
January 1st, 2007 at 9:32 pm
Hi.
I am wanting to find out a little infomation in regards to a blackboy plant that i have in my backyard. The plant is about 6 years old, and this year was the first time it flowered. The plant has always been extremely healthy, but within 1 week it looks like it has started to die. I am unsure if it has to do with the large 8ft flower, if that is draining the plant, do not know if to cut the flower off, or if it is normal for the plant to go brown, which i would doubt, as all the foilage has drooped down to the ground and not standing up. Nothing has really changed in its environment, only climate.
Your help would be much appreciated, as it would be a shame to see this beautiful plant die.
Thanks.
Jamie.
January 2nd, 2007 at 9:42 pm
Hi Jamie,
I have not heard of Xanthorrhoea dying off like you describe. I wonder if you have changed your watering pattern and the plant has received too much water and the drainage is not as good as it was. It seems from everything I have read that good drainage is very important.What a shame to lose a plant so well grown and at flowering stage. It is probably worth while excavating around the plant reasonably close to the trunk to check moisture levels. The root system is not extensive. You may be able to save the plant by cutting foliage back heavily and transplanting into a postion with improved drainage.
June 17th, 2007 at 2:23 pm
Hi,
I would like some information please. We have a Blackboy tree that is 4 metres tall and the trunk is about 2 metres. We know that it must be really old. The 5 heads have been dropping off over the last 3 years. On inspection down the arm where the head fell of it appears brown and muddy. Is this normal? and is the trunk hollow? It would be a shame to loose it.
Thanks
Nigel
June 17th, 2007 at 9:33 pm
It sounds like you have rot in the stems as what you describe is not normal. I would cut below the rot area until you come to solid stem and treat the area with a fungicide such as ‘Fongarid’ or some thing that is available for painting on fruit trees that suffer collar rot. Wash whatever you make the cuts with in disinfectant.
I wonder if the tree is under the canopy of other trees which drop leaf litter and bark? If so and it is possible cut back the overhanging branches. In any case I would regularly clean leaf litter from the crowns. Has the drainage around the root zone of your tree changed? It would be a shame to lose such a well grown tree.
June 17th, 2007 at 10:06 pm
Hi Connie, thanks for your reply does the collar rot progress down the whole trunk of the tree, as it is a very large grass tree. There is no overhanging trees and the drainage system hasnt changed. If you lean on the trunk the whole tree wobbles is it usually that moveable. Would controlled burning be of any benefit we havent tried this we have been in the house for nearly 4 years and the tree was here when we moved in. As you say we would hate to loose such an old tree, and it is a great feature in our garden.
Thanks
Nigel
February 1st, 2008 at 7:36 pm
hello
I’m living in Switzerland. 1 year ago I brought me a blackboy tree. It’s a beauty! Now, since about 3 month, 3 young xanthorreas are growing up realy quick from the ground. They now about 35 cm tall. The mother plant is about 100cm tall. Is it a good or a bad sign? I know, in Switzerland we have a complet different clima than in Australia. Can you give me a few hints for our special cold clima? Thanks a lot for your help!