Pests and Diseases

Physan - or Physan20 as a greenhouse (orchid house) prophylactic

Burton Green — Fri, 20 Nov 2009 16:08:53 GMT

I've used it for 20 years - spray all plants once a month with weak solution ( 1:1000 or as little as 1:5000) to eliminate bacterial rots, black spots, sooty mould etc ; marvellous in a warm humid greenhouse ( orchid hot house, for example).

Also used 1:1000 in stored rain water to prevent algae and keep it sweet - which means that it gets into all water used on the plants and perhaps explains my absence of root rots and similar problems..

But the sale has been banned in UK ( EU Rules). I need a gallon a year - can't afford to go to New York just to get it...

Any suggestions foe a substitute ?

Geoff

Fungus?

Greenfingers — Tue, 17 Nov 2009 22:12:27 GMT

A white "cobweb-like" mat has formed on the soil in a 3meter long container I have in my garden. Would anybody know if this is a fungus of some type and will it damage the plants? Should I remove it?

Birds Nest Fungus

coatgal — Wed, 18 Nov 2009 14:38:39 GMT

I have a Veronica Spicata that is looking worse for wear - black leaves - and underneath there is a cluster of birds nest fungus. Am I right in thinking that the fungus is the result of the dying plant and not vice versa? And is it likely that the Veronica is suffering from too much water given the recent rain?

Insects on a chilli plant? aphids?

Amanda_Cumbria — Tue, 17 Nov 2009 11:55:02 GMT

i brought a chilli plant in from the greenhouse last week without realising it had small insects on it. i put it in my window sill which contained other plants and herbs. as you can imagine, now everything is covered in them, including an artificial flower arrangement!! how do i get rid of them, and are they aphids? ive thrown out the herbs as they were almost done anyways. am i right in thinking if they aren't on a plant, they have no food and will die, or is my house now likely to be overun with them. WHAT DO I DO? help!!!

Fungus gnats!

larunlady — Thu, 05 Nov 2009 16:10:49 GMT

I am having a real problem with these pests (scarid flies). I tried Provado vine weevil killer but doesn't seem to have worked. Also, they are in my chilli pepper plants, in pots, and it can't be used on edible crops. Does anyone have an idea what I could use? I've tried keeping the pots dry etc. but they are infesting the house!

box hedge disease

gardenpixie — Thu, 29 Oct 2009 13:50:30 GMT

I seem to remember reading about a new disease affecting box hedges last year. I think it was a viral disease. I am unable to find anything when I search on the internet. It made the box go brown and then die. Can anyone help with the name of the disease, and if there has been a cure found?

Many thanks.

What's eating my beech hedge??

sallya42 — Tue, 27 Oct 2009 12:57:25 GMT

Can anyone tell me what's attacking my beech hedge? The end plant lost its leaves in the summer and now it's spreading to adjacent plants. The leaves developed small brown spots around the edges, turned yellow and dropped off. no new shoots came through. The stems still appear to be green inside, so I don't think the plant is completely dead. There doesn't appear to be any major insect activity,although some leaves do have some small white bugs on the underside. Will it recover, or is the whole hedge doomed?? Should I trim it back and hope for the best?

Sallya42

Unwanted Fungi in Chipping path

Littleacorn — Mon, 26 Oct 2009 12:15:46 GMT

I have pathways made of wood chipping (laid over black garden weed suppressant material) dividing the raised beds in the vegtable patch, the paths have been in place for three years and in the last few weeks there has been a large amount of fungi growing , i have disposed of this and would like to stop it from re growing, does anyone think it might be ok to water a weak solution of disinfectant over the path , and would this kill off the spores.

What's been eating my Heuchera?

Greenfingers — Mon, 05 Oct 2009 14:05:12 GMT

Came back from holidays and something has been eating the roots of my heuchera from below. The plant looks pretty normal and the soil around it undisturbed but I can just pick it up like a saucepan lid and there are no roots underneath. This has also happened to plants I have had in small pots on the patio. The heuchera is in a large planter with other plants which seem unaffected. Has anybody any ideas what could be happening with it? Photo attached.

Poorly Rowan Tree

hblues — Tue, 29 Sep 2009 15:10:15 GMT

I have a very poorly Rowan Tree which is approx. 7 years old. It has up until earlier on this year had leaves, shoots and berries every year. I have fed this tree with bone meal twice yearly in Spring and mid-Autumn. It is situated on a gentle incline, the dip of which has been quite water-logged for most of the year. There has been no sign of fungus activity and the roots appear firmly attached.

This year it started with small buds which seemed dry up on the branches / twigs early on in March. The upper layer of bark has increasingly showed a whitish mottled discolouration whilst the underneath appears to be have more reddish-brown patches. It has not had any leaves or berries this year at all. I am concerned that it has died or is dying as the branches are now drying out.The other Rowan trees near iton the lower part of the incline show similar problems, while the larger, more established Rowanson higher ground appear to be in good health. Other nearby different species of trees appear healthy.

Last week the upper layer of bark has started to peel off, exposing a reddish-brown underneath and some of the lower branches have dried out completely and snap easily.

Can anyone offer me any advice about how to proceed ? I would like to try save this tree if possible and prevent any other nearby Rowans sucumbing to disease.

Grub eaten away at a fruit tree

BT1973 — Sun, 18 Oct 2009 17:04:09 GMT

We had an apple tree in our garden that has been here many years, ie more than 15 I would think, which died last year. we took the tree down to the stump and left it like that, but this year we have got round to moving it and it came out of the ground with just a little push and crumbled away in front of us! In the base of the tree stump we found some VERY LAREG grubs...about 3cm long white with brown 'noses'..horrible! They seem to have eaten away at the tree and reduced it to sawdust....any idea what they are and if they are a risk to another apple tree close by, also if we can replant a fruit tree in the same position or will we need to get rid of them first....and how do we get rid of them???

Whats up with my viburnum?

ElRosso — Mon, 12 Oct 2009 09:23:11 GMT

Hi, I'm looking for some advice please, I have a couple of varieties of viburnum in the garden and all are looking a bit peaky.

First off, this one which had a number of branches completely die back this year and last, I have pruned them out and noticed this marks on the leaves of the surviving branches:

http://img376.imageshack.us/img376/3481/dscf0042.jpg

There is this other viburum, which hasnt suffered any dieback but the leaves are shriveling up in places (kind of hard to make out in the picture sorry)

http://img195.imageshack.us/img195/5763/dscf0038qo.jpg

I also have a viburnum rhytidophyllum whos leaves are looking a bit droopy and shriveled, but suspect autumn could be a cause of that.

I have also noticed my black elder is losing its leaves all down one side:

http://img360.imageshack.us/img360/9823/dscf0044.jpg

This is a vew from the other, fully foliaged side in comparison:

http://img195.imageshack.us/img195/7150/dscf0045f.jpg

I am in Glasgow and we have had an appalling 3 years of very wet summers and I'm aware that fungal diseases thrive in wet warm weather, the apple trees have had scab this year, box hedging is being destroyed by what looks like blight, diseases resistant roses struggling with leaf spot, pear tree losing its foliage due to leaf spot, sycamores dropping their leaves midsummer with leafspot, mildew on the rhodies - it just goes on. Just like the rain has these last summers...

I was wondering if the die back on the black elder and the first viburnum I pictured (after pruning out dead material, doh!) could be caused by Verticillium Fungus? I suspect a number of fungal diseases at work in the garden, very few shrubs look completely happy, but thats the one I'm most concerned about.

Thank you,

Anyone else noticed a rise in fungal problems due to our wet summers?

Chafer nightmare!

Bill Carr — Wed, 14 Oct 2009 19:07:23 GMT

Hello All, I Wondered if anyone had had a worse problem than me?! 2 treatments of pesticide, and they are still going strong, although not in a bigger number. I'd like to avoid Nemetodes as they are going to be Very expensive with the area I have to treat. Add some overnight crows, and this is what we wake up to every morning!! Any suggestions welcome of how I can treat or get my lawn back!! Thank you Bill http://gallery.me.com/trumpet.mac/100022/IMG_0596/web.jpg?ver=12555467870001

Help! Chilean pine prob!

rohan — Sun, 11 Oct 2009 08:52:43 GMT

Hi. I have a young, still potted Chilean pine that was given to me a couple of months ago. It now looks to be it terminal decline having first developed small brown spots on it's leaves, the branches are dying rapidly from the bottom up. Someone advised me to try bonemeal to encorage root growth to strenthen plant, but no joy.

Could i take tip cuttings to try and salvage something if all else fails?

Thanks for any input.

Catterpillers

Big Phil — Sun, 30 Aug 2009 11:12:46 GMT

Hi all and hope all is well..... I was looking on the internet for a product to kill catterpillers on my strawberry plants and came across Dipel it contains bacillus thurengiensis or BT says its safe to use around bees etc. the problem I have I cant seem to buy it in the uk ??? is they a differant name or product on the market in the UK??

Do you know of a good product that is safe to use on fruit and veg that is bee freindly??

Phil

Euonymus japonica

Mark Keir — Sun, 11 Oct 2009 20:25:28 GMT

In one of the gardens I work in there are two very small sad looking Euonymus japonica. Neither is in a situation I would expect euonymus to find at all difficult and nothing around them is suffering the same problem. They are both no more than 4 inches high and have the remains of just a few leaves all of which look as though they have been attacked by an army of mini-vine weevil. Does any body know what this could be. I did a quick trawl on the internet and came up with Euonymus notching caterpillar or black vine weevil. The notching looks to small for the latter and so far I can't find any mention of the above pests in Britain. Any ideas anyone?

Acer sick!

Patricia in North Vancouver — Fri, 09 Oct 2009 17:18:01 GMT

Hi there,

I live in North Vancouver, BC Canada. Here on the west coast of Canada we have had a very long, warm, dry summer which is still continuing. I noticed about a 3 weeks ago that my 1 year old Acer was looking "stressed". The leaves are curling, are very dry and are falling off. The branches are still flexible and I believe the tree is still alive. It is situated on the north side of my house and receives moderate amounts of sun. I thought I was keeping it well watered through the summer, but perhaps not? I don't see any bugs or apparent fungal disease.

Any thoughts? Thanks for any help you might be able to give me.

Beech leaves with holes

Posie586 — Fri, 04 Sep 2009 18:18:53 GMT

Our huge and old purple Beech, Fagus sylvatica, and many beeches in this area of northern Scotland, are riddled with holes! small 2 mm holes in <every> leaf!! the growth of leaves is generally small, and sometimes rimmed with die-back. Everything seems fine, but if this is some type of shot-hole, how do you treat it? Presumeably some tiny gnawing creature does its damage while leaf is 'furled'. Hedges as well as trees. Sad :(

(Don;t worry about Scotland/isle of Man, thing - I am asking question on behalf of my brother!)

Using Grazers to deter rabbits and deer

AlexS — Wed, 07 Oct 2009 20:56:11 GMT

Hi All, I started using 'Grazers' a few months ago to keep the rabbits and deer from eating bedding plants, roses, etc. (It's a systemic spray which makes plants unpalatable to animals, but is, I understand, non-toxic and safe to use on food crops.) So far, so good - it has worked very well up to now, and I'm really pleased. What I'm wondering is, will it work all year round, when food is scarce? And as the instructions tell me to repeat the spray every six weeks, will it be as effective when plants aren't actively growing? Has anyone got experience of using it for over a year?

Leek Moth

foxglove — Sat, 19 Sep 2009 08:31:44 GMT

Has anybody got any idea please re Leek Moth.

We have had a massive attack on our allotments.Many people have given up , dug them up & burnt them

We on the other hand have not given up, we have cut the tops, squashed the catterpillars & whiped off the cocoons that we have seen. Watered them & fed them. Is there any point in carrying on do you think?[:'(]

Thanks

Help! - My Accacia is losing its leaves :-(

Paul — Wed, 07 Oct 2009 10:47:20 GMT

Dear RHS,

my brother in law, who is a tree surgeon, said to seek advice from this forum regarding problems I am having with my Acacia’s. I have three planted approximately 5 years ago about 6m apart & about 6m high. They were all doing fine up until last Spring when the one in the middle shed its leaves completely but for a small number of branches. I was not to worried as the others that flanked it seemed perfectly fine and my brother in law said not too worry this sometimes happens for no apparent reason. This year the same thing has happened again to the tree in the middle but also the one adjacent left. The one on the right end is vigorous and healthy. Can you help as I am now told there is a disease affecting Acacia in this country and I am worried that I will lose these trees. Is this a known problem and is there anything I can do? I can provide a picture but am unsure how to do it in this message. Any help would be greatly appreciated.

Kind regards

Paul

07770 884676

Bluetits and a lemon tree

Tranquillechat — Tue, 13 May 2008 21:02:56 GMT

It appears that a bluetit (or pair of bluetits) are ravaging the leaves of our lemon tree. Th tree is in a planter on the deck and the lemon tree is in all other respects fine (with lots of tiny lemons-to-be) but since we got it, a few weeks ago, the leaves have slowly but surely been disappearing. One evening I caught the bluetit red-handed, in the process of ripping a couple of leaves to shreds. It looked like it was actully eating them. So far it only appears to go for the older leaves. If anyone has had a similar bluetit / lemon-tree experience or has some advice for disuading the bluetits in some non violent fashion I would love to hear from you.

How can I get rid of Red Spider Mites?

NickR — Mon, 05 Oct 2009 14:10:12 GMT

Hello,

Earlier in the year I had a big problem with red spider mites in my greenhouse, originally thinking it was just spider webs I didn't take much notice until I realised the plants were going yellow and were slowly dying!! By that time around 75% of my plants were covered and I lost most of them [:'(]

I also had a nasty surprise today when one of my houseplants, a lovely red Hibiscus, appeared to have some yellow leaves, at first I thought maybe it was due to the time of year, but on closer inspection I spotted the dreaded red spider mites!! I have many houseplants together on my window sill in the kitchen, so I'm really worried incase the mites get onto them too, but it appears so far that only the Hibiscus had the mites.

I wasn't too sure what to do, but I'm guessing the mites prefer warm conditions, so I put the plant outside in the cold, I cut off all parts that had webbing and mites on them (should I put these straight into my bin?), then I sprayed it with some Rose Clear in the hope that as its an insecticide it might kill the mites!

If anyone can let me know if I did the right thing or not I'd be so grateful, and if there is any advice anyone can give in order to get rid of and prevent red spider mites from ruining my plants! I'm thinking of completely disinfecting my greenhouse in early spring using Jeyes fluid, hopefully that will kill any unwanted mites!

Regards,

Nick R

Glyphosate

David — Thu, 23 Jul 2009 09:12:12 GMT

I have been informed that this herbicide is to be banned from October 2009 and replaced by a product based on the extract of the pelagonium species. I am sure I am one of the last to learn this but do the RHS publish on this excellent value website details of the latest comings and goings in the very fast moving world of herbicide and pesticide developement? I normally find out about such matters when a teenage assistant in the garden centre tells me " that was banned years ago Silly"

grape vine problems

greenthumb — Fri, 02 Oct 2009 02:14:42 GMT

For the past three years, my grapes have had several problems. nice clusters of grapes form but while they are still green and hard, some shrivel and turn hard and black so I thought it might be mummy berry. but there are also some grapes that turn a rusty color and have holes and are hollow and sometimes bits of web are around the clusters. Grapes are completely destroyed before they can even ripen but I've seen no moths or worms. Leaves are untouched but younger leaves turn a splochey yellow while oldler leaves are still a healthy green but I don't know if that's just a nutrient deficiancy. I tried raking up and burning all the leaves and debree last year but it still came back this year.

Any ideas on what I should do? I hate to use a buch of chemicals but I'm not even sure what I'm dealing with.

Any input would be awesome. Thank you so much. :)

Jen