Plant Doctor Archive

Unhealthy citrus tree

WE have just built a new home and have been in residence for about seven and a half months. A friend gave us an 'Encore' mandarin tree which was looking extremely healthy. Over the last two weeks, however, the leaves have started to yellow and drop off. I wondered if it was lime seeping from the new concrete. I don't want to lose this tree but am not sure what to do.

EVERY garden in New Zealand (well, at least where the climate permits) should have a citrus tree. You're certainly on your way, but your tree is not sounding too healthy.

I don't think that the concrete will have much to do with the yellowing of the leaves. Is the plant in a pot or the open ground?

The most obvious culprit is a lack of water. Citrus trees, especially those grown in pots, need to be kept moist over summer. Your tree may also have suffered during the cold spring or it could be lacking food or iron.

If the plant is in the open ground feed with Yates Citrus food, or if in a pot feed with Watkins Citrus Time Release Food, or Nutricote Outdoor & Patio. If you need a quick fix to help with iron deficiency, feed with Epsom Salts. Use each as directed on the packet until the foliage is green.

Reproduced with permission from the former Weekend Gardener magazine. The views expressed here are not necessarily those of the RNZIH.