Help with powdery mildew on very, very old lilac bushes

[LadyoftheRabbits]

This is LizzieGrace. My daughter is logged in right now!

[lizziegrace]

1. This is LG and here's my question:

I'm renting a house that was built in 1846. I moved here in late March and got very sick shortly after and was down for a month. I finally got a coupled raised beds in and am now pruning back all the dead growth on the trees. The apple tree is producing apples with black spots. The pear tree seems okay. The peach tree is all but dead.

The pruning I got to was the lilacs. I have 3 very, very old lilacs. The smallest of the 3 is at least 75% dead. The remaining leaves are covered with what looks like powdery mildew. The middle is 1/3 dead and about 1/2 the remaining leaves are covered. The largest (12 feet tall and just as wide) has few dead limbs but is starting to show some mildew.

I don't want to lose these beautiful old lilacs. We've had very little rain this spring and summer. What's the best way to tackle this. I've hauled the dead growth and infected leaves to a burn pile 1/2 acre from the bushes.

Help??

[beac]

2. I've heard spraying with a milk solution is a good natural cure for powdery mildew.

See:

http://www.associatedcontent.com/article/246855/natural_cure_to_powdery_mildew_pg2.html?cat=32


Your rental sounds lovely. Hope you can revive those lilacs. They are lucky to have you to give them some TLC after such neglect. :)

[Blue Gardener]

3. I tried milk on garden phlox last year

I would say it was semi-successful. I still had some powdery mildew but the plant recovered from it. This year I used one application of Garden Safe Fungicide this spring and the plant is doing great.

[Arkansas Granny]

4. You might try this website to see if they have a product that you can use.

They have environmentally friendly products.

http://www.gardensalive.com/default.asp

[rosesaylavee]

5. I once had a yard that had an entire hedge of very old lilacs

At the time I was subscribed to Horticulture magazine and they luckily had an article about pruning lilacs. Best time to prune is spring of course but this fall would do fine as well. I pruned mine back as recommended in the article - down to the point where the bush was about a foot to two feet tall. Took out all the old growth and then prayed I hadn't killed the poor things. The next spring they were still alive and we only had leaves no flowers. I think by the following year, there were flowers again and the height was about 4 feet tall. It takes a while to see the flowers come back but getting the old stuff out of there and allowing new growth to happen is key. Good luck!

[lizziegrace]

6. Thank you for the advice!

Right now I'm only getting the dead limbs removed. I was afraid to touch the old growth. I'll do some research and decide what to do this fall. Like you, I'll be praying I don't kill them!

[plantwomyn]

9. One of the reasons why you have the mildew

may be that there isn't enough wind circulation. Pruning out the old wood and letting air and sun into the plant will help. So look at your pruning as therapeudic. They may look funky next year but they will be better for it.

[Blue Gardener]

8. Spring blooming shrubs

Have to be pruned right after they are done blooming if you want flowers the next year.

[flying_wahini]

7. I have tried milk, Daconil, and think Liquid Copper is actually

going to work.

We shall see... I have lost 3 huge plumbagos that grew too close to a sprinkler head and subsequently
got mildewed and died in about a month.
I had tried the Daconil and milk and also tried another one whose name escapes me..

this was after pruning for air circulation as well.

Liquid Copper I found at a gardening store, concentrated about 2 pint size -
under $10
considered an "organic".