Faye
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Joined: Mon Nov 07, 2005 8:51 am
Location: Geneva, Switzerland

Grey mould is attacking my garden

Hi

I have just bought (this week) a new house with a garden that has been completely neglected for 5 years. Unfortunately I think there is a serious disease that has taken hold and I need help in understanding what it is - and how to deal with it - hopefully without having to use lots of nasty chemicals.

It is a thick grey mould that covers the bark of some apple trees, privet bushes and lots of other plants. It seems that with a lot of mould, the plant completely dies. The mould in areas turns a deep mustard yellow. Last month I noticed one apple tree had it, but the other on the same espalier structure was fine. I returned this week to find the good apple tree now half-covered with the mould.

How do I stop it killing my whole garden?

It is also in the privet hedge, with whole plants dead, and the mould is now on the leaves and stems of the other bushes in the hedge. I can also see it on the trunks of big trees, and just starting in the quince.

I would really value some advice. My partner and I have been city-dwellers until now and have zero gardening knowledge, but we love this garden and really want to bring it back to life.

Thanks.
Faye

The Helpful Gardener
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Location: Colchester, CT

I would suggest a treatment of neem oil, at the recommended rate, immediately. Keep an eye out for reinfection in a week or so, reapply as necessary...

Keep us posted,

HG

grandpasrose
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Joined: Tue Jun 28, 2005 12:21 pm
Location: Quesnel, BC, Canada - Zone 4a

This sounds like it could be a very severe case of powdery mildew to me..or something related. Scott is right with the neem oil. Also a couple of other organic treatments you could try are:
- In a spray bottle, mix 4 teaspons baking soda, 1 tablespoon horticultural oil, and one gallon of water. Spray the area lightly including undersides of leaves, etc. Don't pore or spray this mixture directly into the soil.

- Mix one part low fat milk with nine parts water and spray every five to seven days.

I would also clean up any dead material lying around and burn it to get rid as much of the fungus as possible. Don't put it in your compost.

Good Luck, and congratulations on your new home! :wink:

Val

opabinia51
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Location: Victoria, BC

Hi Faye, I've been thinking about your mold problem.

Definately do the Neem Oil procedure outlined by Scott and Val. But, here is some information that you may find helpful:

Plant diseases and infections generally occur when plants are somehow stressed. Given that you have the mold on post of your plants and the tree. I am thinking that your soil may be lacking a given nutrient. You could have the soil taken to a local nursery to be tested for nutrient availability and composition but, all you really need to do is feed your soil. In the organics section, (where you have posted this query) there are a few threads describing organic techniques to improve your soil. Definately do these now as well as the neem oil treatment.

Also, at the outset of the feeders on your tree (generally speaking that is just beyond where the farthest branches reach) dig a trench and fill with a layer of leaves followed by a layer of manure topped off with the excavated soil. Provide a layer of leaves and manure around the surface area of the soil as well.

This will provide your tree (and the rest of your plants if you spread the sheet compost on the rest of your garden) with all the nutrients that they need. Thus, enabling them to fight off any opportunistic Fungi are bacteria that are most likely already growing on their surfaces.

Be sure to keep the neem oil treatment up though.

Faye
Newly Registered
Posts: 3
Joined: Mon Nov 07, 2005 8:51 am
Location: Geneva, Switzerland

Thank you very much for all these very helpful responses. I shall try them all immediately.

One further question: It is just starting to turn pretty cold here, with frost on the way. Should I be cutting back all the areas of every plant already covered with the powdery mildew, but presumably therefore risking letting the frost get into the plant, or do I just cut back the already completely dead parts and then spray the alive but mouldy bits with the suggested sprays?

Thanks again - I will keep you posted!

Faye
Newly Registered
Posts: 3
Joined: Mon Nov 07, 2005 8:51 am
Location: Geneva, Switzerland

One further question about Neem oil. Is this something I should expect to find in a regular garden centre? And do I apply it neat with a spray, or do I need to mix it with something first?

Thank you again, from a true gardening novice!
Faye

grandpasrose
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Joined: Tue Jun 28, 2005 12:21 pm
Location: Quesnel, BC, Canada - Zone 4a

Hi Faye! You can cut out all your damaged and dead material and dispose of it now. The sooner you do that, the less there is to spread. Then spray what is left.
Neem oil is an organic spray made from the Neem tree and should be available at your garden centre. If not, then you may have to purchase it on line. It comes in mixed solutions, or concentrated for you to mix with water yourself.
The baking soda/ oil spray is also a deterrent to the fungus. The mild spray is actually putting the good bacteria back into your garden, so that it is more able to fight off these diseases.
Also, as Opa says, building up the soil to be healthy and full of nutrients, will make your plants and trees healthy and more able to resist these attackers!
Best of luck, and feel free to come back any further questions anytime! :wink:

Val

frogesque
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Joined: Tue Aug 23, 2005 5:29 pm
Location: Kingdom of Fife, Scotland: 56.2°N, 3.2°W

As well as the excellent advice above I would also thin out your plants as much as possible and burn everything you cut out if regulations allow. Now is the best time as the sap will be falling. You will have to be brave and bold but get as much air circulating round all your plants and trees as possible. Don't plant too many annuals next year to avoid overcrowding.

If infection is really heavy you may have to resort to sulphur washes in between the neem oil treatments. Sulphur will also help if there are any specific rusts associated with your plants (especially the private hedge) Some lichen can look like disease as well but are generally fairly harmless.

You may also find that aphids and whitefly are partly responsible. They produce a sticky substance called honeydew that a grey/green powdery fungus thrives on and it can suffocate a plant allowing other pathogens to get a hold and finish the job.

grandpasrose
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Joined: Tue Jun 28, 2005 12:21 pm
Location: Quesnel, BC, Canada - Zone 4a

Great info Frogesque! Thanks for adding on! 8)
Val

The Helpful Gardener
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Joined: Mon Feb 09, 2004 9:17 pm
Location: Colchester, CT

All good tips, Faye. And know that MOther Nature will be helping wit those colder temps; fungii hate cold weather...

Scott

dlbm300
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Joined: Sat Dec 03, 2005 4:55 am

Thank you for the tips. They were helpful.

grandpasrose
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Posts: 1651
Joined: Tue Jun 28, 2005 12:21 pm
Location: Quesnel, BC, Canada - Zone 4a

You are very welcome! Feel free to drop in again! :wink:
We'll be here.......

Val



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