6

Are there any known problems with leaving lemons on the tree after they are ripe?

Last year I had a heavy crop and I just picked them as I needed them. The following spring the tree lost most of its leaves and produced only one single lemon this year.

The tree has had problems with yellowing leaves and curling which I (reluctantly) treated with a copper spray and I applied Epsom salts around the base in case of magnesium deficiency. It has also been the wettest of summers in New Zealand, but that hasn't stopped my orange tree or neighbours' lemon trees from producing.

I suspect I sapped the tree's energy by leaving the fruit on too long. Could that be the case?

  • 2
    For me it is soil/fertilizer problem: nitrogen or pH. BTW I found normal that leaves will yellowish in winter. – Giacomo Catenazzi Jul 4 '17 at 15:55
  • I've never seen any kind of stress from leaving citrus fruit on too long. How consistent have the conditions been? You mentioned lots of water. Does the area drain well? You could check for a phytophthora infection in the roots. Have you seen any insects on the stems, leaf undersides, or roots? – J. Musser Jul 4 '17 at 23:04
  • The soil in my garden is clay like and gets waterlogged easi – Aaz Jul 5 '17 at 9:40
  • ...easily when there is heavy rain. BTW it is winter now and the tree has all its leaves back and are not very yellow. Last spring is when it lost most of the leaves and went yellow. There were not many flowers either. Haven't noticed any peculiar insects around the tree. – Aaz Jul 5 '17 at 9:43
3

You are correct to be looking for other causes, and waterlogged clay is a prime suspect. It may be most intuitive if you think about where citrus are native. Waterlogged is a condition to which your tree’s ancestors likely didn't have to adapt.

As for leaving on the fruit, it’s highly unlikely that’s the, or even a, problem. From a theoretical perspective whether it might matter depends on whether the plant is determinate or indeterminate. The distinction labels whether they make all their seeds, including any associated fruits, all in one big batch per year or whether they keep trying to start new seeds all season long. Citrus are determinate. They flower once a year (mostly) and their fruit ripens fairly synchronously.

Once indeterminate plants, which do not include citrus, successfully mature some seeds, they may quit trying to make new ones either for the year or forever. Removing IMmature fruits can sometimes trick a plant into putting energy into a new round of seeds and fruit. That’s why deadheading sometimes can extend flowering, but in this case it’s exactly what you don’t want. Deadheading makes a difference only for indeterminate plants, and while the seeds still have not yet fully matured. Neither applies to your ripe lemons.

About the only real risk in leaving on fruit, besides perhaps a mess on the ground, is that a few of a plant’s pest species may overwinter in the fruit and/or seed. Before I worried about that, though, I’d have a specific pest in mind and it would have to have reached troubling levels too. I suggest spending any time you have for the tree working on better drainage before you fussed over picking off fruit you won’t use.

  • Thanks for your insight, very interesting and great to know that citrus are determinate. If waterlogging is the problem then I wonder why my orange tree wasn't affected? It was suggested to me that some lemon trees fruit every two years. Although that fact seems to be speculation as I haven't found any evidence of this. – Aaz Jul 7 '17 at 20:59

Your Answer

By clicking “Post Your Answer”, you agree to our terms of service, privacy policy and cookie policy

Not the answer you're looking for? Browse other questions tagged or ask your own question.