Michigan2Iowa
Full Member
Posts: 49
Joined: Fri Jan 27, 2006 11:39 am
Location: Cedar Rapids, Iowa, Zone 5a
Contact: AOL

Ashes around Lilacs harming Crocus?

A mystery...

I have been adding wood ash around my lilacs to let them thrive (my double white french-hybrids respond very well)...however the crocus that my wife planted at the base of the bushes are coming up now as we've had a very mild January in Iowa. The tips of the crocus have emerged from under the wood ash and they are brown and disfigured (they look burnt). My wife is placing the blame on me (who else?!?) and my ash. I'm wondering if the ash could cause burn on the crocus flowers, or perhaps the entire colony of corms? My question is could the ash be changing the Ph of the soil to a point that its affecting the corms, or could there be another culprit? The ash can become very dense and wet after a snow-melt...could it be a moisture issue? Do Lilacs not co-exist well with croms/bulbs?

Thank you for your help!

-Paul-

opabinia51
Super Green Thumb
Posts: 4659
Joined: Thu Oct 21, 2004 5:58 pm
Location: Victoria, BC

Wood Ash is low in Nitrogen and higher in Carbon compounds. Unfortunately ashes can contain some deleterious carbon compounds that can harm plants. So, I wouldn't say that the ashes "burned" the crocus per se but, they may have harmed it.

What I would recommend doing instead of adding straight ashes to your plants, mix them with some mulched leaves and a bit of manure. This way both your Lilacs and your wife's crocus will benefit.

(The leaves will dilute any deleterious carbon compounds that may be harming your wife's crocus)

Michigan2Iowa
Full Member
Posts: 49
Joined: Fri Jan 27, 2006 11:39 am
Location: Cedar Rapids, Iowa, Zone 5a
Contact: AOL

opabinia51,

Thank you for the assistance. That does make sense. I do have a follow up question: do you have a recommended ratio of amedments to my wood-ash? I only ash my lilacs, and add about 1-2 inches of the ash over the winter as we use the woodstove.

Thanks again!

-P-

opabinia51
Super Green Thumb
Posts: 4659
Joined: Thu Oct 21, 2004 5:58 pm
Location: Victoria, BC

You are more than welcome.

Let me see, If I had a million leaves......


Oh yeah! Well, ratio's aren't of great importance but, I would say that if you had say 2 parts mulched leaves (apple and maple are the best) to one part wood ash to one part manure, that would be fine.

That will provide a nice slow release of nutrients for your plants. (Add some used coffee grounds and the mixture will help to repel slugs as well. Just add a few more leaves to keep the C:N ratio up a bit)

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

Hi Paul!
Opa has given you some wonderful advice......

A couple of other causes may come into play here as well.
The first is that bulbs do not like to sit in soggy wet soil. They prefer light well drained soil.
The second is that wood ash lowers the acidity of the PH of your soil. If you added wood ash and it made your lilacs perform better, than you probably had acidic soil, which the ashes have corrected.
However, bulbs prefer a PH level around 6-7 or even slightly more acidic that that. So their needs are at opposite ends of the scale.
What you need to do is:

1) ease off on the wood ash a bit. It is recommended that you add wood ash only every 2-3 years in any one area.
2) add some acidic building material around and over those bulbs. Peat moss, or elemental sulfur can do this.
Your wife's crocuses did not get burnt, they just didn't have the right soil mixture for them.

Another cause, could be thrips. Thrips can cause the tips of the buds on the bulbs to become distorted and discolored. They also attack the foliage, also distorting and discolouring it. Thrips are a tiny bug that are so tiny they are barely visible. To eliminate them, spray weekly with either insecticidal soap or neem oil, until the infestation is gone. Ensure that you continued spraying long enought to eliminate any eggs that may hatch as well.

I hope with all these different causes, you can identify the one that is right for your situation. Let us know how this works out for you, and come back any time! :wink:

Val

Michigan2Iowa
Full Member
Posts: 49
Joined: Fri Jan 27, 2006 11:39 am
Location: Cedar Rapids, Iowa, Zone 5a
Contact: AOL

Val & Opa,

Thank you for the great responses. I would have to agree with the acidic soil conclusion...as I have used wood ash every year and the lilacs have responded stronger every year. I will definately cut back on the ash use going forward.

Opa, coffee grounds to repel slugs...I have never heard this before! Is this simply a way to keep them out of the ash amendment, or can this be used in other applications?

Thanks again,
-Paul-

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

You are more than welcome - that's what we're here for!

Add something to those crocuses to make things a little more acidic to balance things out, and you should be okay!

Feel free to drop in again! :wink:

Val

The Helpful Gardener
Mod
Posts: 7491
Joined: Mon Feb 09, 2004 9:17 pm
Location: Colchester, CT

Coffee grounds actually acidify with hummic and tannic acids, great for soil culture. I think thats a great add to ashes...

Opa could ashes be ph base? Could the burn be the other direction here? Or is my shaky chemistry showing? :oops: :roll: :lol:

HG



Return to “Lilacs Forum”