How to treat banana plants turning yellow?

swapnil5137

Hello all, this is my first post, till now I was just looking for answers to pre-asked questions.

I have a "tree" patch which includes a banana, mango and custard apple trees(3-4 yrs old approx), planted by people residing before me.

The banana tree is literally yellow at this point, with new leaves being light green to yellow and older leaves torn, brown and in cases dying.

The mango leaves are slightly yellow, custard apple leaves are forever yellow.

All of this was nice and green last December when I moved in. In January, I painstakingly cleared the mulch and mixed approx 5cm of composted cow manure with the sandy soil and covered with mulch. I fertilised the plants with urea and seaweed fertiliser in March. End of July I added a blend of sulphate of potash, urea, super phosphate, sulphate of ammonia and garden lime. All at half strength to what has been recommended. The trees still look yellow and stressed.

What else do I need to feed them to bring them back to life?

btw, I have another patch at a different corner of the house, and it has lush green leaves for banana, mango and curry leaf trees there.

JacobZ

Hi @swapnil5137,

Welcome to the Bunnings Workshop community, it is fantastic to have you with us.

Your fruit trees are likely yellowing due to nutrient imbalance and soil issues. 

Bananas are heavy feeders and need lots of nitrogen and potassium, but too much lime and mixed salts like urea and superphosphate can throw out the pH balance of the soil which can in turn lock up trace elements such as iron and manganese. Add in the fact that you have sandy soil, which doesn't hold nutrients well, there's a good chance all those added nutrients are being washed away before the trees can put them to use.

The first step is to test your soil pH. Since bananas grow best between 5.5–6.5, you will want to check that the soil is within this range. You can use a Manutec Garden Care Products Soil PH Test Kit to do so. If the soil is outside of this range, you can follow How To Test And Adjust Your Soil Ph to bring it back within this range.

Adding plenty of compost, manure, and mulch will also help to improve sandy soil which will help nutrients stay in place, so keep this up.

Instead of mixing separate fertilisers, use a balanced, slow-release fertiliser such as this Scotts Osmocote Citrus and Fruit Controlled Release Fertiliser. It is much simpler and will ensure the trees are getting the right mix of nutrients.

To give your plants a quick boost, spray the leaves with a liquid seaweed solution that includes trace elements like iron and manganese. Charlie Carp is a good option for this. 

With steady feeding, compost, mulching, and consistent watering, your trees should green up over the next few months.

Let me know what you think and if you have further questions, please don't hesitate to ask.

Jacob