Plant Doctor Archive

Death of lemon tree

Our 'Meyer' lemon tree, which was about 10 years old, has suddenly died. It was laden with ripe fruit when the leaves began turning yellow and withering. We picked all the fruit, but it was too late. Other types of citrus growing nearby are fine and there isn't any sign of borer. What do you think could have caused this? Our soil is volcanic and quite free-draining and we did water the tree during the height of summer, but maybe it should have been more frequent. However, why are the other citrus ok? And is it safe to plant another lemon in the same spot?

Without looking at the plant and conditions, it's hard to pinpoint one specific reason for your lemon tree's sudden death. You say that your soil is free draining, so even though you watered during summer, it may not have been enough. It pays to water for longer periods (up to one hour) at a time every other day in summer. Also, mulching is a great idea as it conserves water, keeps down weeds and the plant is less likely to dry out. Make sure that you keep the mulch away from the base of the trunk.

Even so, it's odd that only one tree has died. Other possible causes include a viral or fungal infection, lack of nutrients or excessive fruit production causing the plant to run out of food for growth. The tree could have suffered from fungal root rot. If so, there's not much you could have done to save it. It's best to dig the plant up and start all over again. Use Yates Basamid Granules in the old place to kill any fungal spores or soil insects. However, I would warn against planting a replacement lemon in the same position.

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