Yellowing leaves on citrus trees
We are testing out the changes we are seeing with the weather by planting some citrus trees, an orange free standing, and in a small wicking bed a lemon. We are relatively high up in midish Victoria and it gets cold here – snow sometimes, frost often, although we are seeing both happen less, so why not try and grow oranges and lemons and see how they go.
This is going to be a new adventure, as citrus trees can be a challenge and do need regular attention. For now, let’s just start with yellowing leaves, which I can spot already! Cause and effect are not always direct, and yellowing leaves does not necessarily mean the tree needs to be fed, although it may. The tree may have been neglected, held too much fruit, and if the tree is in a pot, it may have got its feet too wet. All these can cause yellowing leaves, dieback and a hungry tree.
Yellow leaves, magnesium deficiency, mineral breakdown, wet feet – sometimes just feeding the tree will work, not overnight though. Feed every 3 months as a general rule – so think about the start of each season. Water in, maybe with liquid fertiliser – at half strength if the tree is in a pot. You can water / liquid feed every few weeks – citrus is hungry!
Be aware that if the tree is in a pot, you can easily overfeed it which can burn the root system. Best not to use synthetic based fertilisers for citrus in pots, rather use organic matter, small amounts of compost, manure, superfood, all that good natural stuff.
Leaves that have turned completely yellow will probably not go back to green, instead the tree will drop them and replace with new leaves.
Too much fruit! Is that ever a thing? Well yes, it can be. Leaving too much on the tree can sap its energy. So, pick the fruit as it ripens
Wet feet – citrus trees need good drainage – it will be interesting to see how the lemon goes in a wicking bed! I will keep you posted
Prune - Stimulate the tree as it gets warmer with a light prune. If you already have some flowers on the tree, it will put energy into them, which may take energy away from the rest of the tree. Do you sacrifice the flowers? Well, if the rest of the tree looks as if it is struggling, then yes, you probably should get rid of some, as you should any overripened fruit, any dieback and dead wood.
Saying that, if the tree looks too bad – leaves yellow or defoliated, loosing vibrancy and colour, die back and deadwood, you can give it a good prune, all the way back. It may take a few years for the tree to recover, but it will
But like everything else it is a bit of trial and error.
Enjoy!
Peter