Saturday 24 August 2019

Preventing powdery mildew on squashes, pumpkins and other cucurbits

To my great surprise, I have got this far into the season with hardly any powdery mildew on my squash or courgette plants, despite growing them right next to calendulas that promptly came down with mildew. Every year I fight a losing battle against powdery mildew on my cucurbits that involves removing leaves I spot with it before it can spread and spraying them with water mixed with neem oil or water mixed with milk. None of this has ever worked well in the past. My cucurbits have never made it long enough for their leaves to go old and a bit tatty looking without also having powdery mildew. So what did I do differently this year? Two things:

  1. I have watered them quite heavily almost every day it hasn't rained.
  2. I gave them canes to grow up.

I have, as usual, also removed any leaves where I noticed powdery mildew starting and disposed of them rather than put them on the compost heap (where they would spread their powdery mildew). I can't guarantee this will be successful every time, but this is the first year I've had any success preventing the dreaded mildew at all.
Giving them canes to grow up was quite a hit and miss affair. I didn't really know what I was doing. All I knew was that last year they enjoyed growing up my sweet corn - even though they weren't even supposed to be in the sweet corn's bed. And also, Monty Don gave poles to some of his cucurbits to grow up.
What I initially did was tie tall bamboo canes together in tripods, thinking I would need something really sturdy to cope with the weight of my squashes. Some of my squashes happily latched onto these, but others had to be given a helping hand by tying them on with garden twine.



However, this seems to have been unnecessary, as I later added a couple more canes just stuck in the soil at the front, then the squashes were making their usual attempt to escape the bed and spread all over the grass.
The squash plants have happily latched onto these themselves, just like they latched onto my sweet corn last year. So next year I will simply be sticking bamboo canes upright in the soil all over the cucurbit area. Also, this year I didn't give my courgettes any canes, as the plants looked so compact and bush-like back in early July. Next year I will be giving them canes as well, to see if they're interested. I have really enjoyed having yellow courgettes this year, they're much easier to spot, and this variety has remained tasty and tender to much larger sizes than my previous varieties - which is good, as I never manage to harvest them at the ideal time.
To finish, here are some photos of what else is going on in the garden right now:









No comments:

Post a Comment