citrus post!
Repotting Part Deux
My last repotting post covered all the basics of repotting any general plant, but of course my pride and joy are not just any old plants. Citrus trees require a little special handling.
Here are the materials I'll be using:
Not pictured here is the Osmocote Azalea, Camellia, and Rhododendron plant food, because I forgot about it until after I'd already started and then I was too lazy to take another picture with the Osmocote included. Why that stuff? Because it is a good, well-balanced granular slow-release fertilizer made for acid-loving plants. Citrus are pigs for fertilizer, especially nitrogen, and it helps to have something that releases the nutrients slowly over time. They also like soil that is somewhat acidic, and both blood meal and azalea food tend to acidify the soil a bit.
You'll notice that I'm using a different kind of potting mix this time. That's because I'm potting a different kind of plant. The Pro-Mix I used last time is mainly sphagnum moss, which holds moisture very well. Citrus trees hate to be waterlogged, and so you don't want something that will stay soggy for a long time after it rains. That means that sphagnum moss is out.
Barky Beaver is a brand I've only found in one location - a premium nursery on Westport Road in Louisville called The Plant Kingdom. The internets tell me that Barky Beaver is located in Tennessee, and I don't know how wide their service area is (it obviously makes it up as far as Louisville). It's awesome stuff for citrus trees. It does contain a small amount of fertilizer. This is something you usually don't want, but I forgive its inclusion; you do need to keep that in mind, though, when you are adding fertilizer to the mix.
If you can't find this brand, you will need to either locate or create something of a similar consistency. What you want is soil that retains water but won't get waterlogged and soggy.
The new pot I'm using here is on the left. It's a 12-inch sandy-white plastic pot, sold at Lowes for about $5. The tree I'm repotting is my Eureka lemon, which I bought online from Four Winds Growers in 2006. It came bare-root and about 18 inches tall; I started it out in an 8-inch terracotta pot, upgraded it to the 10-inch pot you see it in there on the right, and am now giving it a 12-inch pot. A plant that is actively growing larger (and which you want to grow larger) is going to need a larger container once a year, but you don't want to go too big too fast. If you do, you'll find it difficult to maintain proper water levels in the soil. Going up by 2 inches in size doesn't seem like that much, but believe me, it's plenty. A pot that's "only" 2 inches larger has considerably more internal volume, and a lot more "leg room" for the plant.
So. Onward!
Step one is to remove the catch tray from the bottom of the new pot. This is one of the big differences between a citrus tree and your average houseplant - you NEVER want anything to prevent water from draining freely out the bottom of the pot. Before you select a pot, make sure that you can remove any catch tray that it may have (although you should probably go ahead and get one that has a catch tray, as this improves the re-use value of the pot once the tree has been upgraded next year).
Buy a separate catch tray, one that's considerably larger than the pot, to set the pot on when you have to bring it indoors for the winter months. When I bring my trees inside for the winter I'll make a post about how to set them up in your house so that they can overwinter in comfort, but you'll be challenged to find a garden center open in October or November selling catch trays. So think ahead and buy one now when you're buying your container.
You also want to make sure your chosen container has lots of good drainage holes. As you can see, this pot has 6 once you get the bottom tray off.
Terracotta pots, with their one large hole in the bottom, are okay if that's all you have on hand and the pot isn't larger than 8 inches, but plastic pots with numerous holes are better. Don't try to use a terracotta pot larger than 8 inches, though, as that single hole isn't enough drainage for a larger sized tree.
A big advantage to plastic is that if you don't see enough drainage, you can cut more drainage holes very quickly and easily with a drill, or very slowly and laboriously with a kitchen knife. It's impossible to add more holes to a terracotta pot.
Now we mix up our soil. You can see here that the Barky Beaver mix looks a lot like mulch. That's because it contains bark chips, among other things. It has a little perlite in it but since this is a general purpose potting mix it doesn't contain enough for our purposes.
So we add some vermiculite. This was 2 single handfuls of vermiculite to 4 double-handfuls of potting soil. Vermiculite looks like fool's gold, which I feel makes it a more attractive soil additive than perlite (which resembles styrofoam balls). However, the two perform the same function and for most purposes they are interchangeable.
Now, if you are an educated sort, you might be saying now, "But Dante, what about asbestos??"
It's true that vermiculite is often found in the company of asbestos, and that the finished product contains trace amounts of asbestos. You would, however, have to be snorting a lot of vermiculite to be exposed to any appreciable quantity of asbestos; if you worked with the stuff daily then you would have a valid concern. For the purposes of the weekend gardener, vermiculite is harmless.
The damage done by the companies that produce vermiculite is another matter and one left up to the individual conscience; if the asbestos angle bothers you, perlite works just as well and costs about the same amount, and you use it in exactly the same way.
Now we add our fertilizer.
The grains that look like bird seed on top are the Osmocote. You actually mix this stuff into the soil so that it's available to the roots. You will also be using it later to sprinkle on top of the soil for late-summer feedings, but working it into the soil is the best way to use it.
Then pour in some water and mix it up well. Get your soil nice and sloppy wet; if you've selected an appropriate container the excess will drain out. When repotting is done properly, there should never be a need afterward to water the plant.
Incidentally, I had to mix up 3 more bags full of soil in addition to this one. That 12-inch pot is enormous.
I then carefully removed the tree from the old pot.
Check out the roots here. You can clearly see all the healthy roots, but you can also see the "potbound" roots. Roots that grow in a circular fashion around any corner of the pot are signs that the plant has gotten rootbound. That ring about an inch and a half up was a corner where the pot narrowed slightly in order for the (removed of course) catch tray to fit onto it. If there is no such thing in your pot, you may find a taproot winding around the bottom corner of the pot several times.
Any such circularly-growing roots need to be unwound if possible and clipped, or broken if unwinding is not possible. In no case can you leave circular roots in place - they will eventually strangle themselves and sometimes other roots in the process.
As with any repotted plant, you should remove as much of the old soil as is feasible, with some caveats.
I removed considerably less than a third of the soil from the root ball; it was pretty compact in there, and you want to minimize damage to the roots while you're removing old soil. Mineral build-up is not as big of a problem in trees anyway, because they get a lot of water flow-through during the summer, which washes excess minerals away. There is still some, so you want to remove as much as you can without savaging the root system, particularly around the top and bottom perimeters, but don't go overboard trying to clean out the root ball.
What's more important than removing old soil here is the idea that you are "fluffing" the root ball, so that the roots will start to grow into the new soil as soon as possible.
Now it's time to put the tree into the new pot. Fill the bottom with some soil, then set the root ball down into the pot to see where the crown sits. In the old pots I really planted them too deeply, and left like 2 inches of empty space between the top of the soil and the top of the pot; that was 2 inches of growing space that the trees didn't have. Don't do that. You want the crown an inch or less below the level of the top rim of the pot. Add or remove soil from the bottom of the pot until you can set the root ball down and the crown is correctly positioned.
Then fill in soil around the sides, tamping it down well as you go to make sure there are no empty spaces. Again, learn from my errors - make sure your tree is in the center of the pot, and standing straight up. Any leaning to one side or the other will make the tree grow crooked, so go slowly and get it right.
Make sure you fill the pot completely up to the level of the crown. Do NOT leave the tree sitting on a hump in the middle of the pot. The soil immediately around the base of the trunk is old soil from the last pot; you want your new soil to come up just to the level of this old soil.
Around the rim of the pot, heap the soil up a little higher. It's hard to see in this picture that I've done that, because it doesn't have to heaped up hugely high, and in fact that would be a bad idea. But you do want the soil to slant slightly downward into the pot. The reason for this is that your tree's roots are located entirely in the center of the pot right now, and so you need water to get to them there. Water that runs down the inside edges of the pot is not helpful, and so you want to heap up the soil at the edges to encourage the first couple of waterings down into the middle of the pot where the roots are.
NEVER plant a citrus tree with the crown underground. The crown must be at the surface, not below the surface, or else you risk tree death.
Finally, we're going to stake this tree.
It may be that you've never thought about staking a plant in a container, but we are talking about trees here, not houseplants. Trees, even planted in a pot, need to be treated like trees and that means they will be outside in the weather.
Think about what you've got here - a plant with a relatively small root system and huge beautiful leaves to catch the wind.
You don't want a really stiff wind to come up and blow your plant over in the pot, or worse yet snap it off at the base of the trunk. However, you DO want your tree to get used to wind and grow to adapt to wind. This means that it must be allowed to sway.
This is the third year that I'm staking these trees, and I hope this to be the last year. The Eureka lemon is getting pretty damned sturdy actually, and so my hope is that next year it won't need to be staked at all. But, so long as you are staking your trees, this is the correct way to do it:
Tie the tree to the stakes as low as possible. Tie it loosely, preferably with something that's stretchy - what I'm using here are strips cut from an old pair of socks. Your objective is not to prevent the tree from moving, but rather to provide some support in the event that it catches too much wind.
Never tie something directly to the tree. Note how the strips are tied to themselves so that they form a loop around the tree and stake. Never tie a knot around the trunk of the tree.
Proper staking is really only possible once the tree is in a sufficiently large pot. Back when they were in 8-inch pots two years ago, I "staked" them by tying them directly to the pots with long strips of plastic, which I cut from one of those flimsy garment bags that they give you at Sears when you buy a coat. The tree's trunk is also tied to the nursery stake that came with the plant, in order to provide a little bit of upright support, but the main support is from the plastic strips.
In case you are wondering, this was done by looping the plastic around the trunk in the middle of the strip, passing the two ends of the strip under the pot, coming up the other side and tying the ends off around the trunk, 180 degrees from where I started. Then repeating this at a 90 degree angle to create the four points of support.
Another method for trees in very small pots is to "stake" the tree by tying it to bricks that you set down on the ground outside the pot.
Be prepared to stake very young trees for 2 or 3 years while they develop a proper trunk, and to change the way that you stake as the trunk becomes more sturdy. Sturdiness comes from stress - a tree that's staked too tightly will never become strong. You want to tree to sway in the wind, but you also want to ensure that if there is too much wind, the stakes will prevent the tree from being destroyed.
Well, that about covers everything I think.
My last repotting post covered all the basics of repotting any general plant, but of course my pride and joy are not just any old plants. Citrus trees require a little special handling.
Here are the materials I'll be using:
Not pictured here is the Osmocote Azalea, Camellia, and Rhododendron plant food, because I forgot about it until after I'd already started and then I was too lazy to take another picture with the Osmocote included. Why that stuff? Because it is a good, well-balanced granular slow-release fertilizer made for acid-loving plants. Citrus are pigs for fertilizer, especially nitrogen, and it helps to have something that releases the nutrients slowly over time. They also like soil that is somewhat acidic, and both blood meal and azalea food tend to acidify the soil a bit.
You'll notice that I'm using a different kind of potting mix this time. That's because I'm potting a different kind of plant. The Pro-Mix I used last time is mainly sphagnum moss, which holds moisture very well. Citrus trees hate to be waterlogged, and so you don't want something that will stay soggy for a long time after it rains. That means that sphagnum moss is out.
Barky Beaver is a brand I've only found in one location - a premium nursery on Westport Road in Louisville called The Plant Kingdom. The internets tell me that Barky Beaver is located in Tennessee, and I don't know how wide their service area is (it obviously makes it up as far as Louisville). It's awesome stuff for citrus trees. It does contain a small amount of fertilizer. This is something you usually don't want, but I forgive its inclusion; you do need to keep that in mind, though, when you are adding fertilizer to the mix.
If you can't find this brand, you will need to either locate or create something of a similar consistency. What you want is soil that retains water but won't get waterlogged and soggy.
The new pot I'm using here is on the left. It's a 12-inch sandy-white plastic pot, sold at Lowes for about $5. The tree I'm repotting is my Eureka lemon, which I bought online from Four Winds Growers in 2006. It came bare-root and about 18 inches tall; I started it out in an 8-inch terracotta pot, upgraded it to the 10-inch pot you see it in there on the right, and am now giving it a 12-inch pot. A plant that is actively growing larger (and which you want to grow larger) is going to need a larger container once a year, but you don't want to go too big too fast. If you do, you'll find it difficult to maintain proper water levels in the soil. Going up by 2 inches in size doesn't seem like that much, but believe me, it's plenty. A pot that's "only" 2 inches larger has considerably more internal volume, and a lot more "leg room" for the plant.
So. Onward!
Step one is to remove the catch tray from the bottom of the new pot. This is one of the big differences between a citrus tree and your average houseplant - you NEVER want anything to prevent water from draining freely out the bottom of the pot. Before you select a pot, make sure that you can remove any catch tray that it may have (although you should probably go ahead and get one that has a catch tray, as this improves the re-use value of the pot once the tree has been upgraded next year).
Buy a separate catch tray, one that's considerably larger than the pot, to set the pot on when you have to bring it indoors for the winter months. When I bring my trees inside for the winter I'll make a post about how to set them up in your house so that they can overwinter in comfort, but you'll be challenged to find a garden center open in October or November selling catch trays. So think ahead and buy one now when you're buying your container.
You also want to make sure your chosen container has lots of good drainage holes. As you can see, this pot has 6 once you get the bottom tray off.
Terracotta pots, with their one large hole in the bottom, are okay if that's all you have on hand and the pot isn't larger than 8 inches, but plastic pots with numerous holes are better. Don't try to use a terracotta pot larger than 8 inches, though, as that single hole isn't enough drainage for a larger sized tree.
A big advantage to plastic is that if you don't see enough drainage, you can cut more drainage holes very quickly and easily with a drill, or very slowly and laboriously with a kitchen knife. It's impossible to add more holes to a terracotta pot.
Now we mix up our soil. You can see here that the Barky Beaver mix looks a lot like mulch. That's because it contains bark chips, among other things. It has a little perlite in it but since this is a general purpose potting mix it doesn't contain enough for our purposes.
So we add some vermiculite. This was 2 single handfuls of vermiculite to 4 double-handfuls of potting soil. Vermiculite looks like fool's gold, which I feel makes it a more attractive soil additive than perlite (which resembles styrofoam balls). However, the two perform the same function and for most purposes they are interchangeable.
Now, if you are an educated sort, you might be saying now, "But Dante, what about asbestos??"
It's true that vermiculite is often found in the company of asbestos, and that the finished product contains trace amounts of asbestos. You would, however, have to be snorting a lot of vermiculite to be exposed to any appreciable quantity of asbestos; if you worked with the stuff daily then you would have a valid concern. For the purposes of the weekend gardener, vermiculite is harmless.
The damage done by the companies that produce vermiculite is another matter and one left up to the individual conscience; if the asbestos angle bothers you, perlite works just as well and costs about the same amount, and you use it in exactly the same way.
Now we add our fertilizer.
The grains that look like bird seed on top are the Osmocote. You actually mix this stuff into the soil so that it's available to the roots. You will also be using it later to sprinkle on top of the soil for late-summer feedings, but working it into the soil is the best way to use it.
Then pour in some water and mix it up well. Get your soil nice and sloppy wet; if you've selected an appropriate container the excess will drain out. When repotting is done properly, there should never be a need afterward to water the plant.
Incidentally, I had to mix up 3 more bags full of soil in addition to this one. That 12-inch pot is enormous.
I then carefully removed the tree from the old pot.
Check out the roots here. You can clearly see all the healthy roots, but you can also see the "potbound" roots. Roots that grow in a circular fashion around any corner of the pot are signs that the plant has gotten rootbound. That ring about an inch and a half up was a corner where the pot narrowed slightly in order for the (removed of course) catch tray to fit onto it. If there is no such thing in your pot, you may find a taproot winding around the bottom corner of the pot several times.
Any such circularly-growing roots need to be unwound if possible and clipped, or broken if unwinding is not possible. In no case can you leave circular roots in place - they will eventually strangle themselves and sometimes other roots in the process.
As with any repotted plant, you should remove as much of the old soil as is feasible, with some caveats.
I removed considerably less than a third of the soil from the root ball; it was pretty compact in there, and you want to minimize damage to the roots while you're removing old soil. Mineral build-up is not as big of a problem in trees anyway, because they get a lot of water flow-through during the summer, which washes excess minerals away. There is still some, so you want to remove as much as you can without savaging the root system, particularly around the top and bottom perimeters, but don't go overboard trying to clean out the root ball.
What's more important than removing old soil here is the idea that you are "fluffing" the root ball, so that the roots will start to grow into the new soil as soon as possible.
Now it's time to put the tree into the new pot. Fill the bottom with some soil, then set the root ball down into the pot to see where the crown sits. In the old pots I really planted them too deeply, and left like 2 inches of empty space between the top of the soil and the top of the pot; that was 2 inches of growing space that the trees didn't have. Don't do that. You want the crown an inch or less below the level of the top rim of the pot. Add or remove soil from the bottom of the pot until you can set the root ball down and the crown is correctly positioned.
Then fill in soil around the sides, tamping it down well as you go to make sure there are no empty spaces. Again, learn from my errors - make sure your tree is in the center of the pot, and standing straight up. Any leaning to one side or the other will make the tree grow crooked, so go slowly and get it right.
Make sure you fill the pot completely up to the level of the crown. Do NOT leave the tree sitting on a hump in the middle of the pot. The soil immediately around the base of the trunk is old soil from the last pot; you want your new soil to come up just to the level of this old soil.
Around the rim of the pot, heap the soil up a little higher. It's hard to see in this picture that I've done that, because it doesn't have to heaped up hugely high, and in fact that would be a bad idea. But you do want the soil to slant slightly downward into the pot. The reason for this is that your tree's roots are located entirely in the center of the pot right now, and so you need water to get to them there. Water that runs down the inside edges of the pot is not helpful, and so you want to heap up the soil at the edges to encourage the first couple of waterings down into the middle of the pot where the roots are.
NEVER plant a citrus tree with the crown underground. The crown must be at the surface, not below the surface, or else you risk tree death.
Finally, we're going to stake this tree.
It may be that you've never thought about staking a plant in a container, but we are talking about trees here, not houseplants. Trees, even planted in a pot, need to be treated like trees and that means they will be outside in the weather.
Think about what you've got here - a plant with a relatively small root system and huge beautiful leaves to catch the wind.
You don't want a really stiff wind to come up and blow your plant over in the pot, or worse yet snap it off at the base of the trunk. However, you DO want your tree to get used to wind and grow to adapt to wind. This means that it must be allowed to sway.
This is the third year that I'm staking these trees, and I hope this to be the last year. The Eureka lemon is getting pretty damned sturdy actually, and so my hope is that next year it won't need to be staked at all. But, so long as you are staking your trees, this is the correct way to do it:
Tie the tree to the stakes as low as possible. Tie it loosely, preferably with something that's stretchy - what I'm using here are strips cut from an old pair of socks. Your objective is not to prevent the tree from moving, but rather to provide some support in the event that it catches too much wind.
Never tie something directly to the tree. Note how the strips are tied to themselves so that they form a loop around the tree and stake. Never tie a knot around the trunk of the tree.
Proper staking is really only possible once the tree is in a sufficiently large pot. Back when they were in 8-inch pots two years ago, I "staked" them by tying them directly to the pots with long strips of plastic, which I cut from one of those flimsy garment bags that they give you at Sears when you buy a coat. The tree's trunk is also tied to the nursery stake that came with the plant, in order to provide a little bit of upright support, but the main support is from the plastic strips.
In case you are wondering, this was done by looping the plastic around the trunk in the middle of the strip, passing the two ends of the strip under the pot, coming up the other side and tying the ends off around the trunk, 180 degrees from where I started. Then repeating this at a 90 degree angle to create the four points of support.
Another method for trees in very small pots is to "stake" the tree by tying it to bricks that you set down on the ground outside the pot.
Be prepared to stake very young trees for 2 or 3 years while they develop a proper trunk, and to change the way that you stake as the trunk becomes more sturdy. Sturdiness comes from stress - a tree that's staked too tightly will never become strong. You want to tree to sway in the wind, but you also want to ensure that if there is too much wind, the stakes will prevent the tree from being destroyed.
Well, that about covers everything I think.