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13 messages
19/06/2012 at 09:40

Help... I have some lovely Hollyhocks in the border which are growing really well, but the large leaves are being infested with rust on the underside.  As a result the leaves curl up and die.  This happens every year, the flower spike develops and flowers well but the plants look odd without their leaves.  What can I do to prevent this happening.  Thanks

19/06/2012 at 09:48

You cant basically-there are rust resistant varieties but  according to reports these also sometimes succumb-unfortunately the spores remain in the soil so if your hollyhock gets it one year it will the next-the best thing to do is to raise new plants each year and then dispose after flowering

19/06/2012 at 10:47

Thanks sotongeoff, it seems a pity to dispose of a plant that has been increasing in size and producing great blooms, but as you say if the spores remain in the soil the problem will persist.  I don't suppose there is any way of destroying the spores that remain in the soil.

19/06/2012 at 11:06

Geoff's right - there's not an enormous amount that you can do about it. One thing I find that helps is to feed the plants very heavily - that encourages them to grow faster, and they can outgrow the rust for a time. You can also try spraying regularly with a fungicide, but will need to add a drop of soap to it to get it to stick to the leaves. Other than that - grow something tall in front of them to hide the bald stems.

19/06/2012 at 11:33

Thanks Alina W.  I shall try everything you suggest as I want to keep these flowers in my garden as the bees love them and they are really pretty when in bloom.  Really striking blossoms which last for ages.  Slugs like them as well unfortunately!!

19/06/2012 at 11:42

I have the same problem with mine, Sterelitza - it's the cost of living somewhere with clean air. Other than the extra feeding, I just ignore it now.

S

19/06/2012 at 15:15

Been spraying mine and it has helped somewhat.

19/06/2012 at 21:48

Mine also have this on them- but I haven't bothered doing anything about it.From the post on here, I'm assuming that rust doesn't harm the plant or flowers just makes it look a bit bald? Which I can live with.

Alina- I'm interested in what you said about it's the cost of living somewhere with clean air. What's your thinking behind this?

19/06/2012 at 21:53

Hollie, you don't get rust if you live in a city - one of the common pollutants in the air controls it. I've known gardens with large patches of healthy, old hollyhocks where the garden was sited on a busy main road.

19/06/2012 at 22:36

I've had to give up growing hollyhocks due to increasingly severe rust each year - so much so that it weakened even new healthy plants within a season to the point that they looked pretty miserable!  Such a shame as I love them, especially as my garden is very much 'cottage' style.  I might give them another try, but in pots, next year, to keep them away from the soil.  Has anyone tried growing them in pots?  They'd have to be staked to prevent the wind blowing them over, although I could try part-burying the pots in the borders to provide stability.

20/06/2012 at 09:44

Yes, I have. They need a decent-sized pot (about 12" diameter), and plenty of water, but they do well.

20/06/2012 at 11:30

Hi BobTheGardner  and Alina W,  thanks for that tip.  I shall try growing them in pots as I really like these plants.

20/06/2012 at 20:26

Thanks Alina, always like to learn new things

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13 messages