My “reward” for going to the Malvern Spring Show last week was the virus Gardening SIL was going down with as we wandered around lusting after plants and planting schemes. So I’ve spent most of the past few days in bed feeling sorry for myself. Even then I couldn’t quite bear to delegate the task of the evening watering to anyone else, so was to be found tottering around the greenhouse and coldframe after dinner spilling water and checking on the squash and tomato plants. Yesterday I finally had the energy to head outside for a spot of gentle planting out of tomatoes, something which I planned to finish today and then blog about – I’m experimenting again. No great surprise there. But as I pottered about on still wobbly limbs clearing up after myself I had my first proper look around the rest of the garden in a while. I’d taken loads of photos for GBBD, but was rather distracted by my new purchases from Malvern. I only took one photo of Knautia macedonica, a plant I have loved and have been raving about ever since I grew it from seed last year. The reddish-purple button flowers float above dissected leaves on wiry stems, and attract bees and hoverflies.

I didn’t include the photo on my post, it was slightly out of focus, the post was already long, even by my standards, and besides, I thought I’d do a post about it later in the year, when more of the flowers were fully open and the Allium sphaerocephalon it was growing alongside was out. I didn’t notice anything amiss, but there again, I was already feeling distinctly “off”. Imagine, then, my shock when I realised this previously wonderfully healthy plant was now looking like this:

This is not a plant that is meant to have silvery foliage. A closer look reveals the strange destructive beauty of powdery mildew.

One plant was entirely silver. The neighbouring ones, at first glance, didn’t seem too badly affected. Wrong!


I was despondent. But double checking what I thought I already knew confirmed that the best course of action was to dig the whole lot up and discard, and not on the compost heap. Not quite the harvest I was hoping for from my garden.

Its largely my own fault. Despite the fact that the word “mildew” conjures up images of damp, dank places, powdery mildew thrives in dry conditions where plants have insufficient air around them. It isn’t really a disease as such, but a fungus. In fact, the one saving grace is that it is a family of fungi with similar results, and each tends to stick closely to its own chosen “victim” – so surrounding plants of a different species tend to be unaffected. I knew back last year that I had planted these Kanutia too close together, they surprised me by their rapid growth, having started out life last April in 3cm pots. The close quarters coupled with the long dry spell produced ideal conditions for the spores to multiply, which they clearly put great energy in to. All three plants had to come out, and then I had to tackle the many self-sown seedlings.

The final tally was three large plants, half a dozen seedlings, filling two large black bin bags. And one disgruntled gardener.
I then had to check on the health of the other seedlings and plants. The plants are on the opposite side of the pond – they appear to still be healthy, although much smaller than their fallen siblings. I’ll keep a close eye on them.

I can tell I am a little paranoid now, as the photo above had me racing downstairs again to check the stems, as they appeared to be silvery. Fortunately just a trick of the light on the hairs that cover the stems. The seedlings are even further away from where the affected plants were growing, and also appear to be healthy. Again, I will be inspecting them closely each time I water them. In the mean time, I now have gaps where there was lush growth.

Although it is tempting to replant more Knautia, I am concerned that the fungal spores may still be hanging around and could destroy the new plants too. I might use the space for some of the Dahlia ‘Bishop’s Children’ seedlings that I was intending to plant up at the allotment. I’ll think about it – I need time to mourn (!) – but this has been a big wake-up call as to just how quickly pests and diseases can take hold in the garden. Never turn your back for long! I begin to dread my next visit to the allotment…
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Sorry you’ve been sick and a fungus attacked your plants as a virus attacked you. I hope the allotment will be in good shape despite your absence. I find that things can suddenly take a turn even when one is diligently hovering while other plants manage survival even neglected.
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I’m trying to look at it as an opportunity to try something else in that space. Won’t get up to the allotment until tomorrow, so will have to stay hopeful for now!
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Hi Janet,
So sorry to hear your Knautia have had to go… I hope the rest survive with no problems :)
I almost bought some at Pensthorpe earlier this week, slightly glad I didn’t now… But I do have a number of Scabious seedlings that are very similar to the Knautia, that too are loved by Bees, Hoverflies and Flutters and I’ve not had any problems with diseases on them. I actually thought they were annuals, so was very surprised to have them come back last year… However this past winter killed them all off so I’ve had to start again.
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Hi Liz, I think I have some more scabious lurking around too, although I think they may be too tall for the space. I’m off on a compost hunt later today so may find myself tempted by something, otherwise it is a mix of cosmos and dahlias, and fingers crossed for the other Knautia. I may plant one in a pot, I think it would look rather good and hopefully the airflow would keep the dreaded silvery stuff at bay. I’ve read that perennial scabious tend to be a little tender and fussy, hope yours make it through this year – I have some deep purple ones that I hope will flower this year and stay until next elsewhere in the pond bed.
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Hi Janet,
I gave in and picked up a Knautia today! I hope it doesn’t suffer from any mildew problems, so I’ll put it in a dampish border so it hopefully won’t dry out :)
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Hurrah! Its perfect for your garden, and you will love photographing the flowers mobbed with insects. Hope it stays mildew free for you.
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Janet, bad enough that you weren’t feeling so good, that powdery mildew is really annoying. We have a large red leafed Sycamore tree in the front garden, a few years ago the leaves turned white and fell off. This year it seems to have recovered completely. Hope all is well at the allotment.
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Hi Alistair, I was tempted to just cut back the Knautia and hope it would recover, but the mildew was all over the plant, including down to the base of the stems, so I decided not to risk it. Glad your tree survived!
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Bad luck Janet. That knautia is usually as tough as old boots (in my experience anyway). So annoying, especially when you’re feeling frail and poorly.
Hope you feel better.
Dave
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Hi David, I was rather surprised, I thought it was a trouble-free plant! Am feeling much better now thanks, ready to plant tomatoes anyway! If I can find some compost…
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What a shame as you say you just need to let down your guard for a minute or two and something takes advantage!
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It was a little galling! And strange how it only took hold after we had some rain. Ah well! I can try something new.
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Sorry to hear about the powdery mildew and the virus. Sounds like you’ve taken care of both, though, and I hope you’re feeling much better. Sounds like the trip to Malvern was enjoyable while you were there. Have fun planting the tomatoes!
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Malvern was definitely worth it, and providing our foray out today provides me with more compost, tomatoes get planted this afternoon, along with the basil. My mouth is watering already!
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‘We will fight them on the beaches and in the hills….we will never surrender’! Glad to hear you have your fighting spirit back Janet! Sorry about your losses but l am sure your gains will soon be upon you.
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That is the perfect quote, thank you! Now if I can just get enough of the work I didn’t do last week because of the virus out of the way I can plant up those new gaps…
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It’s obviously the weather for sickness Janet. Always sad to see plants fall by the wayside especially when they are so beloved. Have cut down a variegated Lonicera similarly blighted and moved it into a more airy place. It’s making a slow comeback as I hope you are. With luck your neglected weeds will have succumbed too.
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Hello Laura, glad your Lonicera is recovering – I have a Cunning Plan to still enjoy Kanutia in the garden by putting some in a pot, that way it will be easy to take with me as well. Making lemonade…
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Oh Janet I am so sorry you have lost your plant. It is a mourning when the plants we treasure most are lost. I too love the Knautia macedonica. Good thing the seedlings are growing well. Here’s wishing you wonderful garden days and wonderful things happening at the allotment.
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Thanks Donna – it is certainly a plant I will make room for again, but I have learnt my lesson, and will both watch it more carefully and give it more space!
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Sorry to hear about your plants but thankful for the information. I had a phlox that got powdery mildew last year and I just left it in place. I’ve never dealt with this fungus before so had no idea of the damage it could do. I’m amazed at how quickly it grew and completely covered the entire plant!
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Shocking, isn’t it! The standard advice is to remove all affected material and either burn it or put it out with the general household rubbish, to prevent re-infection. Hope your Phlox remains blemish-free this year.
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Sorry to hear you’ve been under the weather, I’ve had my daughter ill all weekend too, I think it’s that time of year. What a shame your knautia succumbed to powdery mildew, I always find it even more upsetting when I’ve grown something from seed. Hope the allotment is doing well.
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Hi Jo, funnily enough I think I find it easier to deal with losses when I have grown it myself, partly because I know I haven’t lost as much money, and partly because I know I can replace it. Still not been to allotment…
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I do hope you feel better soon. That really is dedication, looking after the garden when you are unwell. Your comment about mildew and overcrowding inspired my blog post this weekend, and I have referred to your blog with a link. Thank you.
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Hi Ronnie, thanks for the link from your post. I am now looking on it as an opportunity to plant different things in the gaps now revealed.
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Sorry to hear you were poorly after Malvern – not heard of Gardening SIL before. Hopefully the other seedlings will be fine. I have experienced the same problem with sweet peas, gave up with them for a few years but trying again this year.
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Hi Helen, Gardening SIL is the one member of the family who really gets it – this plant thing, that is. BIL was laughably relieved to be able to leave us to get on with it, he manfully attempts to be supportive, and has built Gardening SIL a wonderful pond and an arbour in her new garden, but really, wandering around Malvern would be his idea of hell! Saw Ann-Marie’s garden on the TV last night and thought of you, must be rather special knowing you had a part in what looks like a rather wonderful thing!
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Shame you lost the plants, hope the allotment is OK, we’re off for 2 weeks soon so frantic ‘get everything planted’ activity at the moment. Always interesting to come back after hols and see what state everything is in!
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“Interesting” in the sense of that Chinese curse?! Hope the great planting up goes well and that you have good friends happy to water things well for you in your absence.
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Beautiful knautia, tragic to lose them, and so swiftly! I hope the survivors fare better, and I shall take away your lesson not to overplant but to ensure good airflow – although with the wild winds we have, I would be surprised if anything up here could suffer lack of airflow…
Sara
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Hi Sara, I was really surprised to see it happen like that, and so fast, as they were in a fairly exposed position in the garden. I suspect they were weakened by the long dry spell and then put on too much lush growth too quickly when the rain finally arrived. Just a theory. I will definitely grow it again though, too beautiful not to.
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Oh no! This happened in my garden to a huge planting of filipendula one rainy summer – I thought I’d taken it all out, but the next year a few remnant plants came back, blessedly healthy ever since – maybe that will happen for you.
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Hi Cyndy, good to hear that you had healthy plants come back. I think I am going to stick to the plan and fill the gaps with annuals this year, and perhaps replant with Kanutia next year – slightly less closely!
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What a shame Janet – I love Kanutia too.
There is always something ugly lurking somewhere in the garden, I know the feeling of not wanting to turn my back on the garden
K
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Hi Karen. I think it was the sheer speed with which the plant was overwhelmed that I found shocking. I am generally quite lucky with the health of my plants, perhaps because I always tend to go for robust trouble-free ones in the first place, so unlike slug and snail damage (coriander? what coriander…) this was unusual. But I refuse to give up on Knautia, too lovely to miss out on!
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Hi Janet, I am just testing. My comments are not going through with people using blogger. I just want to see if it goes through with your wordpress. just delete it if it does, sorry to bother you. Alistair
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No worries – I had the same problem with Fay’s blog yesterday, though not any other blogger blogs.
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Ugh! How frustrating! Knautia is one of my favorite plants and I have a pix of it up on my blog. If I had to tear mine out I’d be miserable, too. Hopefully, some seeds will have self-seeded and will provide you with free replacement plants. Hang in there!!
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It is beautiful, isn’t it! Thankfully I do indeed have several seedlings I was already nurturing, though I won’t risk re-planting in the same area this year in case the wretched spores are still around.
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Bad luck on the mildew – we grew it at the nursery and after a while he gave up due to it intermittently getting splattered with it out of the blue.
Hope you’re up to full strength soon!
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Hi Fay, that’s really interesting – I feel better, if a nursery had problems with it too. Full strength might take a while but I’m working on it!
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So sorry to hear that you haven’t been well, Janet; I hope by now you’re feeling better. And I’m so sorry about the Knautia. I’ve found that problems like these spread so quickly that unless you were checking every single day, there’s probably nothing you could have done about it. I think you’re wise not to plant more in the same spot, though. I haven’t checked my garden for the past two days, mainly because we have had constant rain since then. I’ll probably find the weeds have reincarnated themselves:)
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Hi Rose, the weeds always seem to respond to the rain faster than anything else, hope its not too bad! I’ve planted some cosmos seedlings in the gaps, so hopefully the insects will have something nearly as good, just a bit of a break in the food supply.
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What a shame — I’m going out to check mine immediately (especially as I’m about to go away myself). I suppose it’s got a sort-of upside, in that there is that opportunity to do something different…
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Exactly! Admittedly it took me a day to get over the sadness at losing such a great plant, but I have put some cosmos ‘Sonata’ seedlings in the gaps, and a lovely perennial scabious, so not all bad. Have a great break, hope you return to a lush and healthy garden.
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I certainly hope you are now feeling better. I have also been burdened with a cold and my energy level is flagging. The garden, kayak, bike and the dogs call, but I can’t seem to rise to the occasion – well a little gardening. Have you tried any low impact fungicides, like one made with bicarbonate of soda?
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Hi Les, sorry you have been suffering too, it always seems worse at this time of year, when it is the very time you want to be kayaking/cycling/gardening… I’ve not tried low impact fungicides, I’ll look in to the bicarb idea, as I certainly can’t bring myself to write Knautia out of my gardening future!
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Now you have me a bit worried, I am going outside right after this comment. I just planted Knautia last fall in a spot very heavily planted with asters, delphinium, foxglove etc. and, like you said it grows very fast. I may have mine too closely planted and end up with powdery mildew. Boy I hope not since I have yet to see it flower. Great photos BTW.
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Hi Donna, hope you found your Knautia in great health and looking beautiful amongst the asters and foxgloves!
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I’ve just seen the first powdery mildew of the year in my garden – on some sage. Have you ever tried the milk solution method of controlling this fungus? Sounds like an Old Wives Tale to me, but it might just work…
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Hi Mark, sorry about your sage. I still haven’t got around to replacing the one I lost a year ago, though that was to the cold damp winter not fungus the bogeyman… I am currently powdery mildew free, having yanked the plants out, but am intrigued about the milk idea. Sounds smelly…
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Janet – so sorry to hear you’ve been under the weather. I hope you’ve recovered since your post.
Powdery Mildew is a nemesis I’ve been battling on my Center Glow Ninebark for 3 years. I was devastated the 1st year I noticed it – but didn’t even know what it was? I just kept nipping infected leaves, making sure I didn’t touch it with my garden gloves or tools. This year before it started to bud, I cut out any branches that looked diseased. What was left looked small, thin and a bit sad — but now it is so much healthier. I still have been after it, but there is hope! :)
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Hi Shyrlene, sounds as if you are an experienced warrior when it comes to powdery mildew – glad you saved your Ninebark. Am over the virus thanks, but not the after effects – so on an enforced go slow. Not a good time for this in the garden! Am grateful to FIL for his weeding efforts at the allotment.
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Hi Janet, I don’t know why I didn’t see this post when you wrote it, the ‘feed’ usually works. I’m so sorry you were ill, especially at this busy time of year. I’m also very sorry about the Knautia, looking at your photos I’m more convinced that it wasn’t Knautia that germinated for me, and 3 or the 4 plants died when I put them in larger pots and the other looks pretty sad too, I’ll have to buy some seed later in the year and try again and I’ll certainly remember about not planting to close. Hope all is well now. Christina
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Hi Christina, so sorry about your “Kanutia” seedlings, wonder what happened. I can’t even offer to collect you seed from mine, as they are all in the great compost bin in the sky. Hope lots of other things are flourishing in your greenhouse.
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Hope that you are well and truly on the mend Janet. Sorry to hear about the knautia. Same thing here in the dry April with geranium phaeum ~ not a pretty sight. Really enjoyed your Malvern posts ~ sounds as if you had much fun. I smiled at your comment about the tat you noticed on arrival. I think that I have my eyes closed as I make a bee line for the floral marquee on arrival oblivious to all about me.
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Hi Anna, thanks, am over the virus but not the after effects re the ME, but hey, its making me slow down and smell the roses, and ask for help with the watering, both of which will be Very Good for me in the long run… I think I shall have to adopt your “close your eyes and head for the pavilion” next time, and then if there is time and energy enjoy the tat and the non-tat later. So sorry about your geranium phaeum, my favourite geranium, but also the one I am most prone to losing. Hope it comes back for you.
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Hi Janet, Haven’t heard from you for a while. Just hoping you are okay? If you get a minute let us know. All the best, Trevor.
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Hi Trevor, thanks so much for noticing my absence and leaving a comment! I’ve been ill, but I am gradually recovering enough to start dipping my toe back in the blogging waters, and soon, hopefully, will re-acquaint myself with the allotment!