Lemon trees

[Allan.L]

Does anyone know what causes yellowing of leaves on lemon trees? Is it a mineral deficiency?
What can I put on?
Allan

[swerve]

Found this for you.
Looks like its American but will still apply.

There are two possible reasons why the leaves on your lemon tree are turning yellow;

1) TOO MUCH WATER- the tips of your roots might be rotten and can no longer uptake nutrients. You may have poor drainage around the roots or an extremely heavy soil. Citrus need to be watered about once a week and the soil should be kept a little moist but not soaked.

I'd recommend reducing your watering, add about 2 inches of compost around the base of your tree along with 1/2 to 1 inch of composted steer manure, then water it in. The beneficial soil microbes (comprised of bacteria and fungi) in these two materials will help bind soil particles together and allow more oxygen and water to penetrate....this will lead to better drainage, increased uptake of nutrients along with a stronger and healthier root system.

2) LACK OF NITROGEN- Lemons require lots of Nitrogen. Try using a fertilizer with a 2-1-1...or a 3-1-1 ratio.....such as a 20-10-10 that includes magnesium, iron, zinc and manganese. There are several fertilizers specifically made for citrus and avocados that can be found at any of your local hardware stores.

You can also use foliar fertilizers which are applied with your garden hose and sprayed directly onto the leaves. This may be a bit more tedious but foliar fertilizer applications act much more quickly.

Citrus trees prefer to be grown in soils that are slightly acid...around 6.5 pH. If you're not sure what the soil pH is, you can purchase a pH meter for around $15 or $20 and take a reading of your own OR you can call your local Agricultural County Farm Advisor and ask what the soils in your area tend to be.

[swerve]

Try some 15-15-15 from any garden centre. Quince quince quince. I got a 25 kg sack for around €15.00

[El Cid]

And if you want to up the Nitrogen level a bit, buy a sack of Nitrate.

Sid

[Martin Page]

All pretty close ... but none quite on the money.

The problem is Chlorosis

This occurs in most citrus trees that are planted on Chalky soil ( or even where a limestone chipping pile used to be).
You can cure it pretty well with a couple of waterings with chelated Iron which you can get from most good garden centers...in Spainish its - quelato de hierro. Its a very dark red solution when made up and you will need one packet, per tree, twice a year for about 5 years until the tree becomes established.

If you like on chalky soil you should prepare the ground first by digging out a good size hole and filling with Ericaceous potting compost, or leaf mould, or good old peat.to give you a fighting chance.

[Gasman]

Yep - agree with MartinPage - that's what our problem was a few years ago, til we sussed it with advice from the locals. without the correct balance in the soil which the iron helps to sort out, they cannot take up any nitrogen, magnesium, phosporus, or whatever else you give them, so you are on a hiding to nothing until you get the pH level sorted and the iron supplement does it very nicely.

Our problem now is that though the tree looks nice and healthy (and our other lemon tree is loaded with fruit) this tree provides lots of flowers, they set nicely as lemonlets, then the durned things go yellow and drop off while still very small - any advice please? They have both been sprayed agains various bugs and fungi but apparently to no avail for this tree which, on the rare occasions it does get fruit on, gives huge sweet ones (like you see in Cyprus).

[Martin Page]

If your tree is a triplet ( that means it crops three times a year ) you have flowers, fruitlets and fruit on the tree at the same time .... this is a big ask for a small tree .

The late spring set, usually suffers from drying out at the roots and therefor the tree dumps many of the fruitlets in order to ripen the full fruit and prepare for flowering.

Here consistent watering /irrigation will be the biggest help

[Allan.L]

Thank you all for the advice I will try it.
Allan

[Gasman]

Thanks Martin - not sure about all year round triplet style, as on the couple of years where it has produced it only seemed to do one season ... this year it has been flowering since December!! and still has a few new flowers now, along with about 5 nicely set and growing lemons, numerous empty flower sockets where they have dropped off, and quite a few "settings" where they are about 1/2 inch long, going paler by the day, and I expect will drop off soon! It gets as much irrigation as the other trees, including the other lemon tree, which is close by, and looks green healthy and happy
I'll check the watering again ...
Cheers