Author Topic: Yellow-ish leaves on new growth  (Read 873 times)

Olivier

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Yellow-ish leaves on new growth
« on: October 25, 2020, 06:48:29 PM »
Hi,
I've recently started to grow some citrus trees in a grow tent. My yuzu tree seems to be doing just fine except for the very top leaves. They are half yellow.

Because those leaves are almost touching my grow lights, I'm assuming it must be some sort of sunburn symptoms. I wanted to check with you guys to make sure my assumptions are correct. I got into citrus growing only a few weeks ago, so I still have a lot to learn.





poncirsguy

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Re: Yellow-ish leaves on new growth
« Reply #1 on: October 25, 2020, 08:03:35 PM »
New growth is always much lighter green or yellowish.  They will darken with maturity

Olivier

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Re: Yellow-ish leaves on new growth
« Reply #2 on: October 25, 2020, 08:14:54 PM »
Good news then, I was worried for a deficiency of some sort.

Another newbie question, how long does it approximately take for new growth to harden?

lebmung

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Re: Yellow-ish leaves on new growth
« Reply #3 on: October 30, 2020, 04:45:57 PM »
2 months they harden
Your leaves look elongated this is a reason of too much red light in your system and also a root bound issue for containers. Some UV light would be beneficial.
Yuzu is a slow growing plant, they need a cold rest, growing them under lights year round will not give you good fruits.

Olivier

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Re: Yellow-ish leaves on new growth
« Reply #4 on: October 30, 2020, 07:51:13 PM »
Thank you lebmung for the reply.

It's most likely too much red light. My grow light provides mostly red and blue light. My yuzu is my tallest tree and some of the branches were right under the lamp.

I didn't know yuzu needed some rest. I thought hivernating was optional.
I'm also growing buddha's hand, Australian fingerlime and cara cara oranges in that tent. Can those grow all year long without affecting fruit quality?

Millet

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Re: Yellow-ish leaves on new growth
« Reply #5 on: October 30, 2020, 09:30:12 PM »
Many growers, including myself, grow citrus year around.  Almost all greenhouse growers do the same, by supplying heat and lighting their tree until 100:00 PM.   Several years ago I did exactly this with an inground greenhouse Dekopon tree, and received five growth flushes that year.  The tree is now 5 year old and producing many fruit.