You have a beautiful hedge that has lasted for almost half a decade now. However, you are noticing that certain parts of the privet row have started to wilt for no apparent reason.
The leaves of the privet hedge are turning yellow at first, then purple or even black. The decay has started from one side and it is now slowly spreading across the entire length of the hedge… Ligustrum spp. or privet is thought to be really hardy and often survive for years on end without much maintenance. Is this a problem caused by the way in which you took care of your plant, or is it some uncommon disease? Can you do anything to save it?
So, what’s the cause for your privet hedge to be slowly perishing?
The offender here does not always make itself known, although in many cases they do have a distinctive trait – the black “bootlaces” under the bark of the plant. Based on the symptoms, the reason for your privet hedge to be dying is:
A common privet killer – Honey Fungus (Armillaria) – a fungal disease that spreads through the soil. Very destructive in nature, it feeds on the roots of the hedge and leaves them decaying afterwards. Privet (Ligustrum) in particular is highly susceptible to Honey Fungus. The fungi themselves tend to target weak or old plants. The older the plant is, the longer it takes to kill it.
Avoiding damp soil conditions when watering and providing adequate drainage will significantly lower the chances for the fungus to thrive. Poor ventilation should also not be underestimated as it can also exacerbate your fungus problem. In fact, this particular species is to blame for 90% of the privet hedge root rot problems.
Note that it is not necessary for the typical black “bootlaces” to be visible or even present, for that matter. When you are unsure of what you’re dealing with, a smart move is to take a sample of the infected plant and have it tested at a local laboratory.
Treating Honey Fungus outbreaks
Shutterstock / By wavebreakmedia
As these fungi have the ability to vigorously spread underground, there is not much that can be done for the infected plants. Your hedge is already irreversibly ill and all diseased parts should be removed and, preferably, burned. However, you can still save the rest of the unaffected plants. Here’s how to treat honey fungus affected plants and areas:
- Dig out all diseased plants with along with the roots. Dig down to at least 40 cm. This includes even the surrounding parts of the hedge row that appear healthy.
- Get rid of the green waste and make sure not to toss it in the compost bin. Don’t use any of the wood as mulch as it is contagious.
- Remove the infected soil and replace it with healthy new soil. Consider that the disease can be present in up to a metre around the infected plants. Throw away the soil as it has already been contaminated. Here’s an easy way to get rid of the waste.
- Install a plastic barrier in the perimetre of the infected area. The barrier should go at least 45 cm deep into the ground and should surround the presumably infected area.
- Use Armillatox or Jeyes Fluid on the area where the hedges once grew. Dilute your product of choice in water (20:1) and soak the new soil with the solution. These products are known to be the only ones to work when it comes to dealing with what actually kills the honey fungus.
- Wait for at least 8 months before planting anything on this patch of soil. This will starve the fungi to death in case it hasn’t already been completely eradicated by the previous steps.
- Plant a different species of plants that have high resistance to the fungus. There are plants that have rarely been recorded to suffer from this condition and it has only happened if they were already old or ill.
And now, some clarifications…
Want Us To Do Some Garden Work?
We are certified:
What are Jeyes Fluid and Armillatox, and why are they effective VS honey fungus?
Truth be told, there’s no commercially available treatment for honey fungus.
Or at least it is not branded as such.
More than 10 years ago, Armillatox was available as a fungi killer. Its design and name (honey fungus – Armillaria, therefore “Armillatox”) were created for the sole purpose of killing off the fungi. But then the EU banned most acid and tar oil-based pesticides.
The product is now rebranded as a soap-based patio cleaner, but its formula remains the same and just as effective. The same can be said for Jeyes Fluid. Nowadays, an Armillatox or a Jeyes Fluid honey fungus treatment can still be executed – look the products up in your local DIY and hardware stores. When you apply either of these, make sure to avoid direct contact with any part of the plants that are above the ground. Apply to soil only, at a 20:1 water to pesticide ratio.
Are these supposed cleaners potentially damaging to your plants?
As they were once used as pesticides, the formulation of either product is designed for killing fungi and nothing but fungi. Here’s a more detailed answer to whether Armillatox and Jeyes Fluid are really harmful to your plants:
Jeyes Fluid does not kill your plants and neither will Armillatox. Just make sure you use the right dilution rates of 20:1 in favour of water (e.g. 500ml of Jeyes in 10 litres of water). As the sterilisation occurs mainly on the soil, it’s recommended that you use a watering can to apply the solution.
Was this helpful? Give us feedback in the comments below, please!
Header image source: Shutterstock / By Pinkyone
Posted in Garden Advice
Fantastic Services is your one-stop shop for 25+ professional home cleaning and maintenance services, provided within the UK. Using high-grade equipment that is inaccessible to everyday households, the dedicated service specialists will gladly go the extra mile to turn your home or office into something truly special.