297 Christmas Tree Care. Citrus Problems

Garden Basics with Farmer Fred

Tips for beginning and experienced gardeners. New, 30-minute (or less) episodes arrive every Tuesday and Friday. Fred Hoffman has been a U.C. Certifi...

Show Notes

Christmas Tree Care Tips, for both cut and living trees: at 1:36 of the podcast.
Why are the Leaves on My Citrus Tree Turning Yellow?: 9:37
Why are My Citrus Fruit Splitting?  25:22

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Pictured: A Rosemary Christmas Tree Display

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Topic Links:

Flashback Episode of the Week: #162 “Prunecipals: Rose Pruning for Maximum Roses”

Sacramento Digs Gardening Newsletter

National Christmas Tree Association

Yellowing Citrus Leaves (UCANR)

Nutri-Rich fertilizer

Blood meal fertilizer

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Show Transcript

GB 297 TRANSCRIPT Christmas Tree Care, Citrus Problems


297 Christmas Trees, Citrus Probs TRANSCRIPT


Farmer Fred  0:00  

Garden Basics with Farmer Fred is brought to you by Smart Pots, the original lightweight, long lasting fabric plant container. It's made in the USA. Visit SmartPots.com slash Fred for more information and a special discount, that's SmartPots.com/Fred.

Welcome to the Garden Basics with Farmer Fred podcast. If you're just a beginning gardener or you want good gardening information, you've come to the right spot.



Farmer Fred

The sights are festive, this time of year, in the latter part of December, including the parade of cut and shaped conifers, going down the streets, tied to the tops of cars or hanging out the back of pickup trucks. And in the world of outdoor holiday decorations in mild climates, what can be more festive than passing neighborhood citrus trees, showcasing their bounty of oranges, mandarins, lemons and other sweet, healthy treats?

Today, we talk about Christmas tree care. How can you keep those needles looking fresh while on display in your living room? We’ll talk about caring for living Christmas trees, as well. And, those citrus trees may look healthy from a distance, get a little bit closer, and their problems become obvious. We tackle two issues facing many citrus tree owners right now: yellowing leaves, and splitting fruit.

We’re podcasting from Barking Dog Studios here in the beautiful Abutilon Jungle in Suburban Purgatory, it’s the Garden Basics with Farmer Fred podcast, brought to you today by Smart Pots and Dave Wilson Nursery. Let’s go!





Farmer Fred

So are you moving the new Christmas tree around? Or do you have one tied to your car right now, while you're listening? Are you going to put it indoors? Where are you going to put that Christmas tree? And how do you keep a basically dead tree looking green? It just so happens that in a recent article in the Sacramento Digs Gardening newsletter, Debbie Arrington and Kathy Morrison, came up with some ideas on how to keep your Christmas tree looking green. Debbie Arrington is with us. And Debbie, how do you keep your Christmas tree looking healthy, merry and green?


Debbie Arrington  2:11  

Think of your Christmas tree like you would any cut flower: it needs water. And the way to get water is to put it in a sturdy stand that can can hold about a quart of water, at least. The taller the tree, the more water it needs. According to the National Christmas Tree Association, you need one quart of water for every inch of trunk diameter. And so make sure that the stand can hold that much. And then check it every day. Because if the trunk dries out, resin starts forming and it blocks the uptake of more water. And the tree will just dry out like a flower would dry out if the vase ran out of water.


Farmer Fred  2:48  

What about additives? Do they do any good?


Debbie Arrington  2:52  

 Apparently research that the National Christmas Tree Association shared shows that clean water works best. Home remedies, like adding aspirin or bleach or corn syrup or sugar or a can of 7-Up or whatever didn't make any difference. And in fact, the corn syrup and stuff attracted bugs.


Farmer Fred  3:12  

If you are driving home from the Christmas tree lot right now, with that tree tied to the roof of your car, one thing you need to do before you bring it in the house is to shake it out and get all the bugs off. But also maybe cut off a half inch or an inch off the bottom of the tree to allow some clean uptake from that water.


Debbie Arrington  3:32  

Yes, because that resin can block the flow, the uptake of water. It's already stopping its flow where that tree was sitting in a lot, waiting for somebody to take it home. The National Christmas Tree Association actually says that you should cut off at least one inch to restore the flow and let the water come back up.


Farmer Fred  3:47  

And that water monitoring isn't just an occasional check. That's something that you have to check every day to make sure that the basin is full. 


Debbie Arrington  3:54  

Yes, check it every morning. And you'll be surprised how much water that tree took up.


Farmer Fred  3:59  

And that's one of my big issues with a lot of Christmas tree stands. They aren't big enough, so they don't hold enough water. So I would choose a tree stand that could hold probably a gallon of water. 


Debbie Arrington  4:11  

Yeah, if you have a full size six foot tree, you probably do need a stand that will hold a gallon of water. And a gallon sounds like a lot. But if you're looking at a gallon of milk, that's how big of a reservoir you need on that stand.


Farmer Fred  4:25  

Now you've got the tree off the car, you've cut off part of that trunk or that one inch or so, and you've got the stand set up. Where is the best place in the house to put a Christmas tree?  What should you avoid?


Debbie Arrington  4:38  

The best place to put the tree is someplace that will stay cool and away from direct light. Lots of folks like to put their tree in the front window so everybody can see it. But  if that window is facing west or south, it's going to cook the tree. iI prefers  having someplace where it is away from direct light and also away from heat. You don't want to be anywhere near a heater vent, because that just sucks the moisture right out of the tree. If the tree is in a nice cool corner, it will retain its needles much longer. 


Farmer Fred  5:13  

Yeah, that's the key to keeping the needles on the tree. They haven't come up with a cure yet on how to keep cats out of Christmas tree ornaments.


Debbie Arrington  5:20  

No, that's why we have a table top tree, and the cat knows that she can't get up on that table or she's in a lot of trouble.


Farmer Fred  5:27  

And again, I guess the really big point is with the Christmas tree, be it a dead tree or even a living tree, make sure that there is water there.


Debbie Arrington  5:37  

Yes. And that's the thing with living trees. Evergreens don't like to be indoors. And here you've got a big potted  spruce or pine, and you've love to have it inside at Christmas. But it is not in its natural habitat. And it is desperate for light. Evergreens are all full sun trees. They are not meant to be inside where a tropical plant might live. And so if you do have a living tree, give it as much light as possible, preferably in a sunny window, and make sure it gets watered every day. And then get it outside as soon as possible, because it will be much happier outdoors. But when you return it outdoors, don't just plunge it into full sun and freezing temperatures, you've got to gradually bring it back outside, probably on a covered patio,  where it can readjust to outside temperatures and direct sunlight. 


Farmer Fred  6:31  

And you make a very good point. Here we're talking about living Christmas trees that you want to perhaps bring back into the house for the following Christmas. You want to choose a tree variety that is going to like your neighborhood. So choose a variety that is adapted to your climate. And there are some interesting little Christmas trees out there, living Christmas trees that are actually Rosemary plants. 


Debbie Arrington  6:52  

Yes, your Christmas tree doesn't have to be an evergreen. It can be some other kind of evergreen,  that doesn't lose its leaves. A rosemary plant doesn't lose its leaves. It doesn't have to necessarily be a conifer, I guess would be the proper term. You could have lots of different plants  be your Christmas tree. I've seen Christmas tree that are really rosemary. And I've seen different herbal ones, topiary ones, where they they took a privet or some other type of hedging plant and then cut it into the shape of a Christmas tree. You know, Christmas trees  are a decoration. And they are a way of bringing some  of the life from outside to the inside, and make us merry and bright. You can be creative. You don't have to necessarily have a fir as your Christmas tree.


Farmer Fred  7:40  

Exactly. Just buy yourself a good pair of pruning shears, because if it is the rosemary or some other sort of hedging plant, it will need consistent pruning to maintain that Christmas tree shape.


Debbie Arrington  7:51  



Farmer Fred  7:52  

So, put a pair of good pruners on your Christmas list. Debbie Arrington, Sacramentao Digs Gardening is their publication. It comes out every day. And if people want to check out Sacramento Digs Gardening, we'll have a link in the show notes to it. But if you want to do an internet search, how do you do it?


Debbie Arrington  8:09  

Look up Sacramento Digs Gardening. And we were formerly on blogspot, but we're now on Cal local. So look for Sacramento Digs gardening dot California dot local dot com.


Farmer Fred  8:24  

There you go. Debbie Arrington. Have Yourself a Merry Little Christmas.


Debbie Arrington  8:28  

Thank you very much. Happy Holidays!




Farmer Fred  8:33  

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Farmer Fred

It's not just this time of year. It's almost any time of year. Here in USDA zone nine, gardeners are complaining about their citrus leaves. Why are they turning yellow? Yellowing citrus leaves could be due to any number of things, including, shall we say, operator error. Let's bring in somebody who knows something about citrus. That would be Quentyn Young, Sacramento County Master Gardener. 


Quentyn Young  10:04  

As a Master Gardener, I am the project co-lead of the Fair Oaks Horticulture Center demonstration orchard. 


Farmer Fred  10:11  

And in the orchard area at the Fair Oaks Horticulture Center, Q, there are many citrus trees, including a beautiful row of citrus trees towards the back. And I'm sure you see yellowing leaves and you probably get a lot of questions, too, on open workshop days at the Fair Oaks Horticulture Center from people wondering what's wrong with my citrus tree? Why are the leaves turning yellow? And whenever I get asked that question, I would say, “tell me about the yellowing.” Because the pattern of the yellowing is going to tell you a lot about what's wrong.


Quentyn Young  10:45  

That is true. There's lots of online resources where you can actually see the pattern of the yellowing to see whether it's iron, or nitrogen, or magnesium deficiency. There's quite a few nutrient deficiencies, I find that with most homeowners, feeding is sometimes a problem because they don't follow, let's say, the directions, usually. Here at the Hort Center, we feed our citrus in ground once a year, we feed our citrus in containers every month. So depending on where you have the tree can sometimes determine the kind of problems that you might have.


Farmer Fred  11:23  

And add to that the problem of growing citrus in containers, as so many people do. That eases them through the frost season, because they can move the container closer to the house and offer it some heat from a reflected west-facing or south-facing wall. Like you mentioned, if it's in a container, it probably needs to be watered more frequently and fertilized more frequently. 


Quentyn Young  11:51  

That is correct. So I always say follow the directions on what it says on the container depending on whether you're using organic or conventional fertilizers, but follow the directions. But monthly feedings, I found makes a big difference for not just the appearance of the container tree, but also the productivity of the tree as well.


Farmer Fred  12:11  

Is this true with most citrus trees? I think I've had questions on just about every citrus imaginable about the yellowing leaves.


Quentyn Young  12:18  

In containers, yes. In the ground, a lot of it depends on what sort of environmental factors there are. People, I think, sometimes have a bad habit of putting citrus trees in lawns. The trees don't like that. They don't like the regular watering that they get from sprinkler system. If you're putting down lawn fertilizer, let's say too much, or using a weed and feed product, that can affect it. They don't like our heavy clay soils. So if they're sitting in soggy soil, you'll see a lot of yellowing of the leaves. And then going into winter, as the ground temperatures start to cool, the citrus trees have a harder time pulling nitrogen from the soil. So they'll naturally start yellowing. So you'd have to be a little bit prepared for that as well. 


Farmer Fred  13:02  

That's a double edged sword, of course, because if you are seeing yellowing leaves in the wintertime, and your diagnosis is “oh, it's a nitrogen deficiency,” you really don't want to fertilize it when the soil temperatures are so cold. You want to wait until spring. Because if you added that fertilizer now, there could be a salt buildup. And that just results in more yellowing leaves.


Quentyn Young  13:24  

Exactly. And hopefully we'll have a nice rainy winter, then most of that nitrogen is probably gonna get washed through the soil because it doesn't stay around very well. 


Farmer Fred  13:33  

What is your schedule for fertilizing in-ground citrus at the Fair Oaks Horticulture Center?


Quentyn Young  13:38  

We usually wait until the ground warms up. We shoot for March or April, depending on what the temperature is like. And then we'll fertilize. Our stuff is a combination of Nutra-Rich fertilizer, which is a pelletized chicken manure that you can get at most of your local nurseries here in the Sacramento area. It doesn't have very high numbers for nitrogen, phosphorus and potassium, usually it’s a 4-3-2, but we like it because it doesn't burn. But we also use bloodmeal. And the bloodmeal is 13-0-0. And that helps green up the plants for the spring and summer.


Farmer Fred  14:09  

But again, you're only applying it then probably from late winter through what, late summer.


Quentyn Young  14:17  

But we're only doing it once. We used to do two applications. But for now, we just do it in March or April, depending on the weather. And we don't do our second fertilization anymore, because we're trying to follow best practices for the drought. And we don't want to have a lot of new leafy growth that we would have to supplement with additional irrigation.



Farmer Fred  14:38  

And especially this time of year, you don't want that new growth, which might be susceptible to a winter frost. 


Quentyn Young  14:44  

Yes. And again, that's the other debate we're having at the Hort Center. Whether we're going to go through our big ordeal of pulling out all of our frost material and all of our Christmas tree lights because we don't seem to have used them the last couple of years. 


Farmer Fred  14:58  

I'm wondering about that, too. And the new USDA zone maps that have come out, the USDA has updated their USDA zone maps, there is now a 2023 edition. And one thing you can see on these maps, if you compare the 2023 Plant Hardiness Zone map to the last edition, which was 2012, I think you see creeping heat moving south to north, especially in areas in the Midwest and back east that were zone five may now be zone six, for example. 


Quentyn Young  15:32  

Yeah. So we've noticed the last couple of years, even though I haven't covered my citrus, probably at least three or four years, here at my house. We haven't really had any kind of freeze or frost damage at the Hort Center. So  usually around Thanksgiving is when we start pulling out all the frost materials. We still haven't done it yet. And we're still having a debate as to whether we're going to go through that for this year.


Farmer Fred  15:57  

Yeah, it depends on the frequency and the duration, if you will, of colder temperatures in the morning. Generally, if it's just a light frost, if it's only 31-32 degrees, maybe if they're in ground, maybe just watering the trees and mulching them might suffice.


Quentyn Young  16:17  

And ours are pretty awesome, pretty established. We have one very, very young tree but that was the exception to the rule. But all the other ones are probably, let’s see, we planted the last one in 2013, so would be the youngest. So at least most of them are at least 10 years old and older. So the more established they get, the less problem they have with the cold. 


Farmer Fred  16:40  

One of the most common causes of yellow leaves, and we've sort of hinted at it: is overwatering. And if you plant in heavy soil, when soil is continually wet, especially in the wintertime, the roots can't function, so nutrients can't reach the leaves.


Quentyn Young  16:55  

Exactly, they can't get oxygen, and then they get kind of yellow and limp, and you think it needs more water and you just make the problem worse.


Farmer Fred  17:03  

You want to use a soil moisture probe to monitor and water the trees when needed. And if you can let the top three inches of the soil dry a bit before watering again, that would help.


Quentyn Young  17:13  

Especially in the wintertime. Yeah, there's really no reason to be irrigating. We've shut off most of the irrigation of the orchard at this point, except for some of the things in wine barrels that may not be catching natural precipitation, we pretty much shut everything off. 


Farmer Fred  17:27  

If it's in a container, it's a different set of rules.


Quentyn Young  17:31  

Yeah, and I have pretty much maybe 13 or 14 citrus trees at home in pots. I think I'm watering them maybe once every 10 days just giving them a drink to make sure they don't dry out. 


Farmer Fred  17:42  

And you've found this out the hard way. Sometimes the roots of the tree can be blocking the holes in the bottom of a pot. So you need to check those holes, to make sure they're open and the plant soil is draining. 


Quentyn Young  17:55  

That's an excellent winter project or fall project. Look at all your citrus or fruit trees that are in containers, move the container and make sure that the roots haven't grown through the drain holes and become clogged up. Because what will happen is we'll have three or four days of a really good rain, you may not notice it, but that that pot will fill up with water. And then that plant will start to drown.


Farmer Fred  18:18  

And what does it do before it drowns? The leaves turn yellow. And what does a homeowner think? “oh, yellow leaves I better water it.” 


Quentyn Young  18:25  

Exactly. And then you get that really stinky and anaerobic decomposition.


Farmer Fred  18:30  

All right. So, watch your watering. And one little tip for trees in containers is maybe have a gap an, air gap at the bottom. Basically don't let the pot sit on the ground but raise it up. Put it on some bricks or some two by fours or something to have an airspace to let the roots know that there's no soil here. Go back to another place.


Quentyn Young  18:54  

Yeah, perfect idea. 


Farmer Fred  18:56  

the yellowing too, as you mentioned, could be due to a nitrogen deficiency. And that is the most common cause. The leaves throughout the tree might be light green to yellow, with yellow veins. New leaves may be  small and thin, mature leaves might have irregular yellow blotches and then the leaves might turn completely yellow and fall off. The answer to that is, well, nitrogen is a fertilizer. So come fertilizer time, add nitrogen, like you do with bloodmeal.  Now, having said that, I think as a former nursery person, you know the advice that a lot of people want to hear is when they come in and say all the leaves on my citrus tree are turning yellow, what's wrong? What can I buy to stop that? Somebody might try to sell them a bag of iron or an iron based fertilizer. And because they're saying it's chlorosis which is an iron deficiency, but that's  a different kind of yellow isn't it?


Quentyn Young  19:56  

Is a different kind of yellow. And that's why I always say  look at the picture guides on the internet to try to match your leaf to that. Sometimes chlorosis does happen here in Sacramento, usually in tandem with alkaline soil. The more acidic the soil, the more easily accessible the iron can be. So maybe test your soil, maybe use something like Ironite, it has soil sulfur in it. So it'll also help acidify the soil. So it really just depends. You have to ask a couple questions to figure out what's going on. 


Farmer Fred  20:30  

Yeah, and I think the key to determining that it is an iron deficiency is if the plant leaf has yellow leaves with green veins, if the veins stay green, then chances are, it might be an iron deficiency, but we should emphasize that it's not necessarily a deficiency of iron in the soil. It's the process of getting it from the soil to the tree via the roots. That might be the problem.  And that again, would be due to, like you mentioned,  too much alkalinity or excess salinity, which might be due to over fertilization.


Quentyn Young  21:11  

 Yeah, it depends. A lot of it depends on location. Where are you, what's your soil like? 


Farmer Fred  21:14  

When you choose a fertilizer for citrus trees, if you buy one specifically made from citrus, chances are that fertilizer will have micronutrients in it that might contain iron, zinc, and manganese. But it's I think it's important to remember that  only helps the new growth, it's not going to be absorbed by the older leaves.


Quentyn Young  21:32  

That is correct. Again, my citrus trees, the ones in the containers, get fertilized every month. Like you said, use a citrus fertilizer, because the micronutrients are really important. 


Farmer Fred  21:44  

I mentioned zinc and manganese deficiencies, because both those deficiencies can be prominent, especially in new growth, where you might have pale green leaves with dark green veins, or maybe yellow mottling between the green veins. And you might see some dieback as well. 


Quentyn Young  22:01  

That's true. And again, it depends on where you are, the age of your citrus tree, what your soil is like, what your irrigation is like. If you take take those leaves into a nursery, hopefully they'll ask lots of questions like that.


Farmer Fred  22:15  

Right. And we should point out, too, that when we say manganese, we're not talking magnesium, that's a whole other problem. But that can affect citrus as well. A magnesium deficiency has yellowing that begins at the leaf edges and the tips and it progresses inward, then eventually the entire leaf is yellow, except for a green inverted V at the leaf base. 


Quentyn Young  22:37  

Yeah, then I find that most homeowners will overthink these things. But again, look at the picture guides on the internet. Most people don't have as complicated of these problems as they think they have. 


Farmer Fred  22:52  

And let's not forget, speaking of operator error, if you're spraying weed killer, and that herbicide you're using might have glyphosate in it, you could end up with some pretty funky looking citrus leaves.


Quentyn Young  23:06  

That's correct. And if you're putting down a lot of weed and feed lawn products, as well, because your citrus tree is in the lawn, you could also have some problems.


Farmer Fred  23:16  

Right. That's why we always recommend  if the only place you can plant that citrus tree is in the middle of a lawn, you want to clear out that lawn probably for a diameter of six feet, at least. And just have mulch underneath the citrus tree.


Quentyn Young  23:31  

Yeah, don't try even putting flowers under the citrus. They have very delicate surface roots. They don't like competing with other plants.


Farmer Fred  23:39  

Once again, it's all about the soil. It's all about the water. Those yellowing citrus leaves could be any number of things. We'll have a link to the University of California site that has pictures of these yellowing leaves and what possibly may be the cause, so look for that in the notes for this episode. Sacramento County Master Gardener Quentyn Young, thanks for helping green up our citrus trees. Q, thanks for all your help today.


Quentyn Young  24:06  

Thanks for having me on, Fred.




Farmer Fred  24:13

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Farmer Fred

We like to answer your garden questions here on the Garden Basics podcast. Debbie Flower is here, America's Favorite Retired College Horticultural Professor. Here in California, and in many parts of USDA zones 9 and10, people grow citrus trees. And this time of year, you may start seeing citrus split. And that's a question that comes in from Mary Jane, who doesn't mention where she lives, but probably somewhere where you can grow citrus. And she says,  “Hello, I read your valuable information faithfully. But this is the first time I am contacting you for advice. My fabulous navel orange tree has oranges about the size of tennis balls now, but several of them are splitting open long before maturing. What is your take on that situation?” And again, ladies and gentlemen, if you're writing in with a garden question, please tell us where you're writing from. So we can better arrive at the correct answer. Because, for all I know, Mary Jane, you live in a condo in Milwaukee, and you're growing this indoors. Could be, but I doubt that probably wouldn't happen indoors. Unless you really mistreated that plant.


Debbie Flower  26:34  

Change what you're doing. 


Farmer Fred  26:35  

So I'm thinking that this orange tree is growing outside. And you live in USDA zone nine.  Generally, splitting occurs with wild swings in the weather combined with irregular irrigation and erratic fertilization. My go-to answer when this is the problem and it’s an abiotic disorder, is to add mulch. Mulch mulch, mulch.


Debbie Flower  26:57  

I agree with all that. Except, be careful how much you mulch you place right under the tree. When I was doing some consulting, I visited numerous citrus trees that just weren't looking good. That was what the people would tell me. “They just don't look as good as they used to.” They're getting some extra yellow leaves and such. And all the trees I saw this way had  branches almost to the ground. And I got on my belly and climbed underneath those things, and found that a tremendous buildup of mulch, typically, citrus leaves that had fallen off, because evergreen trees do lose their leaves over time and collect around the base of the trunk. And I cleaned those away from the base of the trunk and the trees got better. 


Farmer Fred

And we all lived happily ever after. 


Debbie Flower

So that's something to monitor on a citrus tree, you don't want the mulch, even if it's natural mulch of the tree, dropping its own leaves to collect up around the trunk of the tree. But two inches of mulch is an excellent idea. Right under the tree. 


Farmer Fred  27:54  

Yeah,  I probably should extend that mulch from maybe two inches away from the trunk, all the way out to the outer canopy of the tree.


Debbie Flower  28:00  

Right, keep that trunk clear. 


Farmer Fred  28:01  

So that can moderate soil temperature and soil moisture. Because citrus, navel oranges especially, split. It’s due to the wild swings in probably moisture, heat, wind.


Debbie Flower  28:15  

So the citrus trees flower in spring, and you have that lovely fragrance all over the yard. And then they set fruit and then the fruit get bigger and bigger and bigger. And around early Fall, in September or October, the rinds the of the citrus are formed and fully sized. And if the fruit inside gets a mass of water infusion, and that can be due to fertilizer, because fertilizer dissolves in water and causes more water to go into the fruit. Or it can be because, especially with climate change, we're getting massive rainfalls all at once. So you can get a whole lot of water all at once. And that pumps the water into the fruit and the fruit gets so big it causes the rind to bust. 


Farmer Fred

(long pause) I’m thinking. 


Debbie Flower

I see the smoke. Yes.


Farmer Fred  29:07  

Other problems too that can cause fruit to crack like that would be if it's a young tree because maybe the roots are more shallow and the tree is rather small. If it has a small shallow root system and the trees are grown in very sandy or poor soils that don't retain moisture well. They may be more susceptible to fruit splitting. Again, maybe it's growing in a raised bed. And again, you've got to think of raised beds like you would a large container plant, and provide more moisture, more often.


Debbie Flower  29:40  

Right. And citrus are good container plants, if you use a half barrel. But when you water it, the media gets really wet. And then when it dries out, it gets really dry. It goes from extreme to extreme. And that kind of thing can lead to the splitting fruit.


Farmer Fred  29:55  

I have a premonition you're about to use the phrase, “weekly, weakly.” Fertilizer can also be a problem, too, if people overfertilize. That can cause splitting as well.


Debbie Flower  30:06  

Yes, it can. It causes the plant to act differently because there are now salts in its water environment. And so that can lead to extra water getting to the fruit and causing splitting. 


Farmer Fred  30:18  

I'd like to point out, too, at this point that when we say salts and fertilizer, both inorganic and organic fertilizers have salts.


Debbie Flower  30:24  

They have to. That's the way the nutrients are dissolved in water. And they travel to the plant and through the plant. It has to be in a form that can dissolve in water. Salts dissolve in water. So it's just the chemical makeup of the nutrient. It doesn't mean it's sodium chloride that would kill the plant really fast.


Farmer Fred  30:41  

I'm going to pull out this “weekly, weakly” tooth as long as it takes me. So how do you fertilize a citrus plant in a container? 


Debbie Flower  30:49  

Well, you said it: weekly, weakly. Use citrus fertilizer, okay. And I'm only aware of granular citrus fertilizer. How about you?


Farmer Fred  30:58  

I use Fish emulsion on everything. 


Debbie Flower  31:02  

Okay. And that works?  A somewhat critical thing with citrus is you need micronutrients, which would be present in fish emulsion. If you're using a refined fertilizer that you buy in a bag that's made for citrus, you'll notice if you look at the active ingredients that there are micronutrients in there, including iron and manganese and those sorts of things. A general fertilizer is not always the best thing for citrus.


Farmer Fred  31:26  

What about time released fertilizers?


Debbie Flower  31:29  

I use time-release fertilizers for convenience. They will say that they last for 30 days or 90 days, something like that, that time that they listed on the label. And the media is moist, and at about room temperature for that entire span of time. So if it's a container that's outside in the summer, and the container gets up to 90 degrees, it's going to release more fertilizer than it would if it was colder. Or if it's a cool spell it will release less fertilizer, in many cases that coordinates with the growth of the plant. But typically on the hot end of it, not so much. 


Farmer Fred  32:06  

If you see splitting oranges on the tree, probably the best thing you can do is remove them. Because that's an entry point. Right?


Debbie Flower  32:15  

Absolutely. And even if they fall to the ground, they should be disposed of. Sanitation is huge in the garden. That broken fruit will grow, let's say funguses that can get into other fruit on your tree, or bacteria or attract those slugs. Slugs and snails love citrus, and that split gives them access to something to eat, and give them a nice introduction to your tree.


Farmer Fred  32:36  

Roof rats have good noses too. They could spot it, too. It's also an opening for diseases like alternaria rot and other fungi and bacteria.  If you got splitting oranges, get rid of them.


Debbie Flower  32:50  

If you're using time release fertilizers, I would put half as much as is recommended in the container and then watch the plant for deficiency symptoms. Add more as you see any deficiency symptoms.


Farmer Fred  33:05  

So, there you go, Mary Jane. Yes, orange splitting does happen. And it's not one thing. It's not necessarily your fault, but it's an abiotic disorder. So whether it's weather, it's the watering, it's the fertilization, treat your plant well. Mulch mulch mulch.




Farmer Fred  33:29  

In USDA Zones 8, 9 and 10, it’s Rose Pruning Season! And soon enough, after frost season passes, everyone across the country will be faced with the challenge of tackling an overgrown, aging, rose bush. How best to prune that rose bush to regain maximum rose production? That’s our Flashback Episode of the Week, Rose Pruning for Maximum Roses. We talk with Master Rosarian Charlotte Owendyk. We’ve got rose pruning tips, as well as advice for the best tools to use and clothes to wear while pruning those prickly roses.


If you missed it, give it a listen. It’s our Flashback Episode of the Week, Episode 162, originally aired in January of 2022. It’s entitled “Prunecipals: Rose Pruning for Maximum Roses.”  Find a link to it in today’s show notes, or at the podcast player of your choice. And you can find it, along with a transcript, at our home page, garden basics dot net.



Farmer Fred

The Garden Basics With Farmer Fred podcast comes out once a week, on Fridays.  It’s brought to you by Smart Pots and Dave Wilson Nursery. The Garden Basics podcast is available wherever podcasts are handed out, and that includes our home page, Garden Basics dot net, where you can find transcripts of most episodes, as well.  Thank you so much for listening…or reading.



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