kumquat leaf yellowing

[andrewq]

hi!

my kumquat leaves have started to yellow since the weather started warming up. is this a sign of disease or vitamin deficiency or sunburn (~8-10h full sunlight, picture taken standing south of the container)? this tree has been extremely reliable and proliferator the past 2 years, giving two harvests each year.

the kumquat is a couple years old and currently in a 20g container. the "soil" is basically 100% cow manure from Home Depot and was fertilized last year with some generic fertilizers and Npetunes Harvest 2-3-1 kelp/fish emulsion. I'm debating either putting it into the ground or reporting it with 5-1-1.

[mrtexas]

Not enough fertilizer.

[Millet]

Citrus generally don't do well when fertilized with organic fertilizers.  If the last time you fertilized was last year, then you are greatly under fertilizing the tree.  Find a fertilizer with higher levels of nitrogen and potassium, and a lower level of phosphorous.  I use a 25-5-15 (5-1-3 ratio) fertilizer and it does very good. Your tree definitely  has a nitrogen deficiency and probably also a deficiency in potassium.

[Viking Guy]

My Kumquats are the hungriest out of all the citrus I have, and I have a lot.

I just about have to spoonfeed the kumquats potassium and nitrogen, and lots of foliars.  There are foliars I alternate weekly and they love it and respond within days to each feeding with flushes of growth, flowers, fruit, etc.

You fertilized last year and growing in 100% cow manure.  Your tree is very hungry, stressed, and you might have some root damage.

I'm finicky about what I grow my citrus in and make my own soils out of a concise combination of mixed particulates.  You must get her on a steady feeding and I suggest a different soil medium for starters.

[Millet]

Another point.  Cow manure is not a good product to use in container growing.  Cow manure does have some nutrition content, but it also has a high level of soluble salts.

[andrewq]

thanks for the info. I was keeping my lychee on a low fertilizer regimen and did the same w the other container plants.

I potted it before I found these forums and the houzz container growing forum and now have been making 5-1-1 and 3-1-1 for the plants and the repotted ones have responded happily.

I have been using low doses of Dyna Gro Foliage Pro the past month for all my plants and Just added some fertilizer (5-3-6) i had in the garage to the citrus. Also have a big bag of Osmocote plus in the mail.

Do you think I should supplement with a foliar spray? Have some Southern ag citrus foliar spray left over from last year

[Viking Guy]

Yes, when I get home, I can list my foliar program for you.  I keep mine premixed, so don't remember all the names, but I use a lot of different products--some can go together as well.