I love my citrus trees but around this time of year they always look a little worse for wear. Scale, leaf minor and mineral deficiencies take a hold and if I don’t find the time to attend to them they get pretty sad looking. I know from working and walking around different neighbourhoods that I’m not alone so if you’re citrus aren’t looking as happy as they could here’s the ever useful White Oil remedy:
- White oil. You can buy it but it’s easy and kind of fun to make. White oil will take care of any sap sucking insects including aphids, scale and leaf minor and now is the perfect time to use it. Because it’s an oil based spray you don’t want to use it when temperatures get high (no worries there in Sydney at the moment) but you will have to reapply if it rains (again, no worries in Sydney at the moment). To make white oil:
2 cups vegetable oil (some organic gardeners only use sunflower oil because there is no chance it could be genetically modified)
½ cup washing up liquid
Put both in a jar and shake it up. (This is the fun bit where you learn why it’s called white oil)
Store in cool, dry place and dilute two dessert spoons per litre of warm water. I dilute mine in a spray bottle and try to use it first thing in the morning Try to spray both sides of the leaves.
If white oil isn’t your thing or your citrus need a little more love, here are some other ideas:
- The toothbrush. Never underestimate the power of an old toothbrush and giving your plants a good going over if the problem and tree are small.
- Feed them.
o For mineral deficiencies you’ll need to feed them iron in the form of iron shelates. You’ll know your tree needs iron if the new leaves are yellow.
o If the older leaves are yellow with green veins then you have a magnesium deficiency. The usual remedy for this is Epsom salts (buy it from the supermarket). I did read somewhere that this may increase the salt content in the soil but I’ve never been able to verify it so for now I still use Epsom salts.
o If they just need a general feed try compost or cow manure around the base of the tree (but not right up against the trunk) or a liquid seaweed solution, rock dust or urine. Yes, fresh, diluted urine is a great fertiliser for citrus.
Don’t be scared to give your citrus a trim (particularly if you have citrus gall wasp – see photo at the top). Citrus can be pruned for shape and health though this is usually done after fruiting. Ok, I think that’s all for now. I’ve got to go spray my trees again.