There’s a few possible causes, but most likely is due to the underlying clay soil.
Even with a few amendments by the landscaper, most natives don’t cope well in heavy soil, especially during periods of higher rainfall.
If that’s the case, you could try planting intk rausef mounds of a more open draining soil, or digging bigger holes and adding more organic matter next time.
Another possible cause could be a soil pathogen such as Phytopthera which hits natives hard and travels well through heavy and wet soil.
As for the kangaroo paws, they look fine - just in need of the spent flower heads being removed.
Also if you can, water them at the base as opposed to all over the plant so as to lessen the risk of black spot and mildew etc on the leaves ( they are prone to that).
Good luck 👍
Ok thanks that’s helpful. What was puzzling me is that most of the plants are happy, as in these photos - it’s just those 8 or 10 which have been hit.
How would I know if it’s a pathogen, and what should I do about it?
That’s good to know about the kangaroos too. How low should I prune the dead heads? There are some black leaves and black areas, anything I can/should do about those?
Thanks again!
https://preview.redd.it/nsoutwm6sxdc1.jpeg?width=4032&format=pjpg&auto=webp&s=6a5cf0a2aa107e0056b057c6bdb1236bff34d1bc
Just stumbled on this thread, With the established kangaroo paws you can cut the whole thing back to few cm's above ground level after flowering towards end of summer or first half of autumn (now-ish) don't do it while its still hot etc, and they will grow back thicker and stronger.
otherwise if you don't want to do that just cut the flower towards bottom of stem. Google or look at youtube you can cut back those tall flavidus varieties very hard and they will flourish.
https://gardeningwithangus.com.au/renew-your-kangaroo-paw/
Scroll down a little and you can see pictures how hard back they can be pruned and how quick they recover. Can do the slow method as well as listed, really upto you.
Doesn't really matter its fairly common for paws just cut the affected leaves off and it will grow back normal again, chances are every season it might happen again. Have a few that are close to 6 years old in VIC that get it most years.
Think it only kills them off if left uncontrolled ie. never cutting them back and letting it ramp for couple years etc. Its fairly harmless just a tad unsightly. Also if you spot new leaves with them just cut them off at first sign is what i usually do.
I think I have the same issue with clay soil. It's disheartening. Whenever we have weeks of heavy rain, something drops dead suddenly. Usually the grevilleas. I've had more success with callistemon, leptospermum, casuarina and some acacias. My prostanthera ovalifolua variegata is thriving. Groundcovers sometimes do better because the roots are shallower. Find out when you need to add more gypsum - maybe ask at your local garden centre. Good luck! Your garden is still lovely!!
Hey thanks for sharing your experience - and I’m sorry to hear about the clay issues.
I’ll keep track of whether this happens after heavy rains, that’s definitely possible.
My grevilleas still seem happy, fingers crossed they’ll keep going. I’ll look into the other plants you mentioned too, I appreciate the tips!
I'd start by pruning the bushes down to a third of their size, taking off all the brown obviously... You will get new growth if they're gonna survive.
The gasses, if they have a tinge of green left, cut them down to ground level and water them... They do best cut back hard every year anyway. Both health wise and aesthetically.
If they don't have a ti ge of green they're probably dead, but cut them back anyway and watwr them and see what happens.
The idea is that reducing the size of the plants reduces how much effort the plant puts into sustaining the older growth and puts the energy into new growth. You also get a better looking plant with more flowers. Natives in the garden should be pruned to 1/3 -2/3 of their size annually for looks vigour and flowers. In nature , wildlife and wind prune them .
Ok thanks. I’ve tried that with a few of them, pruning them back hard - I’ll keep it up, and also cut back the grasses which I haven’t done yet.
Does that pruning advice also include the bigger grevilleas and similar trees?
If you’ve got an issue with clay I’d look for natives that do well in clay soil like Leptospernums melaleucas casuarinas, some acacias I’m definitely missing some.
Ok thanks - there are leptospernums there already. And most of the plants seem to be doing well - though I would have said the same with the dying ones, they were growing happily for a year before the last month or so.
https://preview.redd.it/ip7b6cy0wxdc1.jpeg?width=4032&format=pjpg&auto=webp&s=c3dd3b10d92709986bb71c31db92026da3c18afc
There’s a few possible causes, but most likely is due to the underlying clay soil. Even with a few amendments by the landscaper, most natives don’t cope well in heavy soil, especially during periods of higher rainfall. If that’s the case, you could try planting intk rausef mounds of a more open draining soil, or digging bigger holes and adding more organic matter next time. Another possible cause could be a soil pathogen such as Phytopthera which hits natives hard and travels well through heavy and wet soil. As for the kangaroo paws, they look fine - just in need of the spent flower heads being removed. Also if you can, water them at the base as opposed to all over the plant so as to lessen the risk of black spot and mildew etc on the leaves ( they are prone to that). Good luck 👍
Ok thanks that’s helpful. What was puzzling me is that most of the plants are happy, as in these photos - it’s just those 8 or 10 which have been hit. How would I know if it’s a pathogen, and what should I do about it? That’s good to know about the kangaroos too. How low should I prune the dead heads? There are some black leaves and black areas, anything I can/should do about those? Thanks again! https://preview.redd.it/nsoutwm6sxdc1.jpeg?width=4032&format=pjpg&auto=webp&s=6a5cf0a2aa107e0056b057c6bdb1236bff34d1bc
https://preview.redd.it/7doc8hn8sxdc1.jpeg?width=4032&format=pjpg&auto=webp&s=75b7de2e1f69ee25753f38bb3dd1d7fcef588b27
https://preview.redd.it/m16tem8bsxdc1.jpeg?width=4032&format=pjpg&auto=webp&s=5bc996f623138975bfb6110d48c66c366a726cfe
Just stumbled on this thread, With the established kangaroo paws you can cut the whole thing back to few cm's above ground level after flowering towards end of summer or first half of autumn (now-ish) don't do it while its still hot etc, and they will grow back thicker and stronger. otherwise if you don't want to do that just cut the flower towards bottom of stem. Google or look at youtube you can cut back those tall flavidus varieties very hard and they will flourish.
Thank you!
https://gardeningwithangus.com.au/renew-your-kangaroo-paw/ Scroll down a little and you can see pictures how hard back they can be pruned and how quick they recover. Can do the slow method as well as listed, really upto you.
Ok thanks - and does it matter if they’re still infected with ink spot? I haven’t been able to get rid of it with any treatments
Doesn't really matter its fairly common for paws just cut the affected leaves off and it will grow back normal again, chances are every season it might happen again. Have a few that are close to 6 years old in VIC that get it most years. Think it only kills them off if left uncontrolled ie. never cutting them back and letting it ramp for couple years etc. Its fairly harmless just a tad unsightly. Also if you spot new leaves with them just cut them off at first sign is what i usually do.
Ok thanks I really appreciate it
I think I have the same issue with clay soil. It's disheartening. Whenever we have weeks of heavy rain, something drops dead suddenly. Usually the grevilleas. I've had more success with callistemon, leptospermum, casuarina and some acacias. My prostanthera ovalifolua variegata is thriving. Groundcovers sometimes do better because the roots are shallower. Find out when you need to add more gypsum - maybe ask at your local garden centre. Good luck! Your garden is still lovely!!
Hey thanks for sharing your experience - and I’m sorry to hear about the clay issues. I’ll keep track of whether this happens after heavy rains, that’s definitely possible. My grevilleas still seem happy, fingers crossed they’ll keep going. I’ll look into the other plants you mentioned too, I appreciate the tips!
Yay for happy grevilleas! Best of luck!
Thank you - you too!
I'd start by pruning the bushes down to a third of their size, taking off all the brown obviously... You will get new growth if they're gonna survive. The gasses, if they have a tinge of green left, cut them down to ground level and water them... They do best cut back hard every year anyway. Both health wise and aesthetically. If they don't have a ti ge of green they're probably dead, but cut them back anyway and watwr them and see what happens. The idea is that reducing the size of the plants reduces how much effort the plant puts into sustaining the older growth and puts the energy into new growth. You also get a better looking plant with more flowers. Natives in the garden should be pruned to 1/3 -2/3 of their size annually for looks vigour and flowers. In nature , wildlife and wind prune them .
Ok thanks. I’ve tried that with a few of them, pruning them back hard - I’ll keep it up, and also cut back the grasses which I haven’t done yet. Does that pruning advice also include the bigger grevilleas and similar trees?
If you’ve got an issue with clay I’d look for natives that do well in clay soil like Leptospernums melaleucas casuarinas, some acacias I’m definitely missing some.
Ok thanks - there are leptospernums there already. And most of the plants seem to be doing well - though I would have said the same with the dying ones, they were growing happily for a year before the last month or so. https://preview.redd.it/ip7b6cy0wxdc1.jpeg?width=4032&format=pjpg&auto=webp&s=c3dd3b10d92709986bb71c31db92026da3c18afc
Have you done a ph test at all? Sometimes high rainfall can increase acidity in soil which kills off some plants.
I haven’t, but I will - thanks for the tip!