Lavender 'infection' what to use?

twopenny

I have 4 huge standard Lavenders that have been happily growing to give me privacy so over 4ft now.

With the stress of the drought and heat wave one got loose from it's moorings in the dry soil and started with a sudden die back.

I've lashed them back to upright, they look a tad better but the die back is patchy so still ongoing.

Having said that the branches arent dead (yet) but the leaves are. It's tried to reshoot without sucess.

The other plants are now showing black sooty covering 

which talking to a helpful garden centre guy says needs to be sprayed with a fungicide.

Overjoyed there was a chance to save them I forgot to ask which one!

Can anyone recommend please?

Bear in mind I don't have a special sprayer and it's a big job.

Would love to save them as they aren't available now (pandemic first plants available after lockdown.) and I love having the bumble bees all over all day.

Even a quick growing hedging plant would take a few years to get me the privacy again.

ArbitraryRandom

I think you can use any plant fungicide (they come in spray bottles), but potassium bicarb and copper sulphite are the 'organic' options - so you could look for something with those ingredients. 

You should probably also remove all (or as much as you can) infected material (down to clearing the ground around the plants) and consider trimming out some of the growth to help airflow. 

EDIT: googling this is a nightmare because of the use of lavender oil for foot problems... seen some things this morning I wish I hadn't  

twopenny

Thanks Abs.
No chance of cutting out as it starts at the bottom of the branches and won't regrow.
But I'll see whats about for fungicide. Any excuse for coffee and scones 

Yup, lavender good for foot probs but I don't want to see other peoples 
Teatree is great for athlete foot and I found clears up a shell cut really well.
A couple of things I found out in Australia when they tried to sell me expensive stuff.

ElaniArtin

Try some  other places for plants and grow a couple in pots as back up... Etsy and that other one...

Having said that, I have optimism that they will come back next year fine- As Arbitrary said cut it all back and clear around it -maybe use pretty pebbles instread.  A strong plant will fight off anything. Maybe in spring check the soil ph and ammend the soil. Seaweed fertilizer is just the best stuff!  Your plants are really big so may have used up all the soil around... pile manure on them now, but keep the main stems clear. Mulch thickly before hot weather.

Also keep checking for ants as they will nest under dry plant roots and this will stress the plant.

I love the bees too!

twopenny

Thanks Elani, they are in that place to provide privacy so moving wouldn't be an option.
At their age they aren't going to make it anyway and at that height would quickly blow out of the soil.
Cutting back also isn't an option. Ive tried on a part and it just died.
Only one variety can be cut back and regenerate and that's hidcote.

It's due to extreme drought and extream wet our weather has been and that's not getting any better
Off to the garden centre to see what they have. I'm not hopeful as it's Christmas stuff mostly but we'll see.

Farway

twopenny said:

Thanks Elani, they are in that place to provide privacy so moving wouldn't be an option.
At their age they aren't going to make it anyway and at that height would quickly blow out of the soil.
Cutting back also isn't an option. Ive tried on a part and it just died.
Only one variety can be cut back and regenerate and that's hidcote.

It's due to extreme drought and extream wet our weather has been and that's not getting any better
Off to the garden centre to see what they have. I'm not hopeful as it's Christmas stuff mostly but we'll see.

I'm having to wait now until Spring, when the supermarkets start stocking for summer plants.

Say "Hello" to the singing reindeer at the GC for me

twopenny

So good fortune! I managed to get 2 real experts and they agree, Sooty Mould.
Can't rub iit off because of the furry leaves, not right time to spray.
Aparantly started by a bug that injures some leaves and it's the sap oozzing out and getting mouldy.
Needs to be sprayed when the bugs are active.

It often affects Bay Trees apparently. My pyramid one is just 2ft away 
But should be easy to wipe off.

A comment was, with the weird weathers all sorts of bugs are getting blown over, coming from world wide through travel and now it's warmer ???? They survive. 

ArbitraryRandom

twopenny said:

Thanks Elani, they are in that place to provide privacy so moving wouldn't be an option.
At their age they aren't going to make it anyway and at that height would quickly blow out of the soil.
Cutting back also isn't an option. Ive tried on a part and it just died.
Only one variety can be cut back and regenerate and that's hidcote.

It's due to extreme drought and extream wet our weather has been and that's not getting any better
Off to the garden centre to see what they have. I'm not hopeful as it's Christmas stuff mostly but we'll see.

If the infection is starting from the base, can you take some cuttings from healthy looking sections for succession planting? 

Just thinking worst case scenario. 

twopenny

Thanks for the thought Abs but making 5-6ft standards takes loads of time and skill
I did stick some cuttings out the back and they grow like wildfire but as bushes. The whole standard thing is a skill I don't have and goodness knows I've tried with all sorts over the years.

Hopefully it will sort itself out over the winter if left alone.
If not it's trellis fencing while some privet grows.

Think I was lucky they survived so well through storm and blizzard so far.

One grown from a cutting out back is sprouting new growth from a pruned branch when it definitively shouldn't have. 
If it ever stops raining I may try some intervention     

Dustyevsky

Growing anything as a standard seems to put extra strain on the plant. Take fuchsias, more adapted to our variable but essentially wet climate than lavender, which is Mediterranean. They often fail to regenerate properly after a few winters, getting too woody. That's my experience, anyway. I've got olives as standards, and one out of three went completely bare last winter. It's recovering, but not providing much cover yet. The easiest Mediterranean plant as a standard, I find, is bay. That 'only' takes about 6 years to form a good head!

twopenny

True Dusty.
I remember when I started gardening that it recommended replacing lavendder every 3 years which I dutifly did with great results.
But I find that those out back that I grew from cutting s are also now infected.
Not a chance of replacing them as they aren't available and would cost a bomb now.
They were ten pounds each from Tesco straight after the first lockdown when no other plants were available.

Privet is a poor replacement but thats another thread