Cankers, oozing sap, fruit scab, fruit rot, leaf spots or leaf curl are all signs bacteria or fungus are ruling the roost in your orchard. Today, I want to look at three ways to manage these infections:
- short term remedies of copper and lime sulfur
- long term holistic loveliness
- cider vinegar to the rescue
We don’t need to be purists here – they can all tag team. A robust system takes a good few years to build, so until you get there (garden Nirvana I call it), the vinegar or fungicides are a useful tool.
Cider vinegar may be the miracle bullet we seek. I’m new to spraying it on fungal infections so I’m responsibly waiting and watching how it goes before raving to you about it.
1 Tablespoon per litre. I spray in the evening, or after rain – some say or early morning – others. As far as other ‘rules’ go like how often, I’m just winging it. Heres what other edible backyarders are saying “…sprayed 2/3 times a week and cleaned all the leaf curl from my peaches and they went onto crop well”, “My peaches went down with brown rot three years in a row, I stumbled on cider vinegar as a possible solution and no more brown rot! I spray them every month through the growing season”, “I have used ACV (apple cider vinegar) on all my fruit trees for years and have greatly minimised black spot in apples and hardly have any leaf curl in stone fruits. I spray at the first sign of infection a few times a week”.
Have a go and as always – do what feels good. Watch and learn.
Fungicides are powerful medicine. They’re very good at their job, but there is a trade-off. They are non-selective, meaning they wipe everything out – the bad and the good (think antibiotics).
If resilience and less intervention are what you’re after – then you’ll be wanting to build the beneficial bacteria, fungus, nematodes et all, to the point where there is little room for the bad guys. To the point where your good guy army is too strong for the pathogens to get a foothold. While you build and create this thriving environment, it’s a big call to make – to wipe everyone out, but sometimes that’s what we need to do.
Though it’s a kind of two steps forward, one step back moment, fungal/ bacterial problems are tricky beasts to bring back to balance. I wouldn’t spray copper for a little problem, but once they get a bit of a foothold (recurring annually or impacting a big chunk of the tree), nip them in the bud – I say. Copper those oozy, scabby, spotty trees.
How To Use Copper
It’s so important to use these big impact sprays in a timely manner. Do not copper when blossom is out. Copper is super toxic to bees.
- One spray at leaf fall.
- Two sprays late winter/ early spring. Timing matters. Do the first one when the fruit buds start to fatten up, before the slivers of pink show themselves. Do a second spray a fortnight later.
- Spray for full coverage – in all the nooks and crannies.
- Spray on a dry, still, mild day.
- Wear a mask and sunnies.
- Follow the dilution rates to the T.
- Don’t mix copper with any other spray. (Rainguard or other ‘stickers’ are cool to mix in.)
How To Use Lime Sulfur
- Spray while trees are dormant.
- Wear old clothes, a mask and sunnies and be prepared for the rotten egg smell!
- Spray on a dry, still, mild day.
- Follow the dilution rates to the T.
- Don’t mix lime sulfur with any other spray.
Lime sulfur is an age old fungicide and does an excellent job of cleaning up serious health problems. It will burn foliage off so only use while trees are fully dormant and not on Apricots who are really sensitive to it.
Buying these things can be mind blowing, and the labels aren’t helpful unless you are a scientist. Contact Sarah at edible garden is my advice. She sells the stuff she uses in the nursery. The good stuff.
A Pathogen Prevention Plan (Building A Strong System)
Prevention is possible. And it looks like this
Give your trees access to the nutrients they need, when they need them – from bud movement through to fruiting. Do this with
- Free draining soil. Super important! This is something you need to sort before your trees go in. Wet soils have no air and tree roots need air for nutrient exchange/ uptake.
- Humus rich soil is another key, do this with an annual layer of compost beneath the mulch in autumn.
- The addition of a full spectrum mineral fertiliser and gypsum in spring.
- Mulch with a woody type mulch to retain moisture, prevent fungal splash back and stimulate a healthy fungal zone.
- Bits of log left beneath your fruit trees are an awesome way to promote good fungus. Double the benefit and plug some shitake dowels in them.
Strong cells and active soils make for robust plants that are better equipped to cope with any conditions.
Will it be dry? Will it be wet? Hot? Cold? Windy? these things we just don’t know and can do nothing about.
Will we be strong – this we can do, this we can count on.
Biological sprays do your trees and the eco system around them the world of good. A fruit trees version of eating sauerkraut and organic vegies!
Spray for complete cover – bark and foliage, also the soil beneath – go nuts! You can mix the following sprays together in any combination for a lovely bio brew. A good back pack sprayer makes your spray go further and makes the job easy.
If you only have a few trees to spray, oceans organics sells a handy little spray pack that clicks onto the end of your hose.
- EM or active aerated compost tea beneficial organisms to out-manoeuvre and out-compete detrimental fungi and bacteria. These fellas will speed decomposition so that leaf litter and fruit mummies disappear by spring when they become potentially dangerous. They boost ‘good’ fungi for balanced nutrition.
- Neem – disrupts pests feeding/ mating abilities whilst safe for beneficials
- Seaweed or hydrolysed Fish – for thicker cell wells, good all round nutrition, pest prevention, stronger roots via biological boost, for all round improved access to nutrient and immune boosting
- Nitrogen fixers provide an ongoing nutrient exchange for free! It’s smart to use them. Grow clovers and or legumes on your orchard floor or nitrogen fixing shrubs/ trees throughout or on the border.
- Deep rooting companions like comfrey, chicory and dandelion recycle nutrients, open clay and hold sand – they’re value is enormous. Comfrey beneath your trees saves you the job of mulching and brings a nutrient exchange like no other.
- Plenty of herbs and flowers to discourage pests with scents, and to feed beneficial insects and bring below ground diversity for a larger pool of biological life.
Light and air
- Plenty of light makes for productive wood.
- Airflow prevents moulds and fungus and assists pollination.
- Prune and space your trees well.
- Clean your pruning tools after pruning each tree to prevent the spread of disease.
- Burn diseased prunings
- Feed diseased fruits to your pigs or chooks or better yet get them under your trees in Autumn.
The right variety and rootstock
Varieties that suit your climate and soil are an important strategy. Varieties that don’t match will struggle and become pest and disease magnets. Rootstocks too, must suit your soil conditions. Peach will struggle in clay as will plum in sand.
Ask at local nurseries, neighbours or the garden club. Golden Queen peaches, for instance, are for the Hawkes Bay. Not for me – too much spring rain = leaf curl.
Prune in dry weather only and don’t be too hard (or too soft) – just right 🙂