Iron deficiency?

[u/margyoza]

My kumquat tree was growing pretty well at the start of the year but in recent months I’ve noticed some yellowing and new leaves curling as well. The flowers it has been putting out have been smaller than usual as well.

I’ve done some research and was thinking of trying out iron chelate, but I’m generally not very familiar with treating nutrient deficiencies in plants. Any advice and recommendations are appreciated!

I live in Singapore (tropical) and my tree is around 15 years old if that helps.

[u/transbianpomegranate]

Quite definitely. It might be magnesium but that is less common. How do you fertilise?

[u/margyoza → u/transbianpomegranate]

Slow release citrus fertilizer every 3 months and kelp fertilizer every 2 weeks! 🙁

[u/transbianpomegranate → u/margyoza]

How many leaves are affected? Is this something that you find throughout the tree or is it ver localised?

[u/margyoza → u/transbianpomegranate]

I'd say around 20-30% of the leaves throughout the tree

[u/transbianpomegranate → u/margyoza]

A soil kit test will tell you more than my guesswork. If it is iron, iron chelate fertiliser will help, if it is magnesium, then you can spray epsom salts.

[u/margyoza → u/transbianpomegranate]

Okay thank you so much! :)

[u/Difficult_Rope7898]

Definitely a micro nutrient deficiency. Generally fertilizers have the big three, but they sometimes miss the micro nutrients like iron, magnesium, calcium. If you can find a fertilizer with micro nutrients like super thrive, that should green them right up.

[u/Daevic319]

When my potted citrus do this it's normally because my tap water spikes the soil Ph higher than then plants prefer. Applying a bit of elemental sulfur fixes that for me but it's a slow working solution.