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Repotting

Improving drainage in a compacted rootball

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Midway through repotting a procumbens juniper, I found that the center of the rootball was dry. This is common when a tree has gone too long without repotting. Even heavy and frequent waterings – or incessant rain – may not be enough for the water to soak the entire rootball.

Rootball with dry center

Finding dry patches of soil during repotting is great as addressing the problem is easy. Bare-rooting sections of the rootball is one option for improving water’s ability to pass through the soil. Another is creating holes in the rootball.

Creating holes with a root hook, chopstick or old screwdriver loosens up the rootball enough to let water pass by more roots during watering and makes it easier for water to soak into the remaining compacted areas. For this tree, I used a root hook to create a hole.

Using a root hook to perforate the rootball

I worked from the top of the rootball and the bottom until I’d removed a section of soil about 1.5″ across.

A hole in the rootball

I made several similar holes around the rootball, being careful not to damage too many of the exposed roots in each hole.

After preparing the rootball for repotting, I tied the tree into the pot and began adding soil.

Rootball secured into the pot

This is where it can be helpful to remember where the holes were created. I filled each hole with loose soil and used chopsticks to settle the new soil into place.

Hole filled with bonsai soil

After settling the soil in the holes, the level of the soil dropped a bit so I added more soil and repeated the process until the holes were full of fresh soil.

After settling the soil in the hole

After refilling and resettling the soil

When the chopstick work was complete, I mounded some soil above the rootball and tapped it into place. Here’s the tree freshly repotted.

Procumbens juniper after repotting

As noted in the previous post, the new pot isn’t perfect, but it’ll do well as I continue to refine the tree. I expect I’ll tilt the tree further to the right at the next repotting, but hesitated as I didn’t want too much of the rootball to rise above the edge of the pot as I’d already removed a number of roots during this repotting.

I’ll let the tree settle into the new pot for several months and then get to work on the foliage. Feeding will begin in about a month.

How to secure bonsai in the pot

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When I first heard that bonsai are commonly wired into the pot I thought, “That sounds crazy – you must be kidding me!”

Over the years I’d planted hundreds, if not thousands, of plants in containers without wire for a retail nursery. The practice sounded extraneous and made me think that bonsai people were overly concerned with such details.

I quickly learned, however, that my thinking was misguided.

One reason for this is that garden plants tend to stay put after they are planted. Bonsai, on the other hand, are frequently moved around.

We move them throughout the year so all sides of the tree can get equal sunshine. We move them into a workspace when it’s time to prune or wire. If we join a bonsai club, we may take our trees to workshops or exhibits. All of this movement provides ample opportunity for bonsai to jostle around in the pot.

Because bonsai are often planted in course soil mixes, it takes little pressure to knock an unsecured bonsai out of the pot. Large trees with undeveloped roots can even blow over in the wind when not properly secured.

Even when our trees don’t move or blow around much, subtle movement of the tree in the pot can break fine roots and stress or weaken bonsai. Before we can wire bonsai or carve deadwood, we need to make sure our trees are securely held in their containers.

How to secure bonsai in the pot

Bonsai pots come in many shapes and sizes. Almost all of them, however, have drainage holes so excess water can easily drain out. (If your bonsai pot doesn’t have drainage holes, drilling one or two will make it much easier to care for your trees.)

A variety of bonsai pots

Despite the great variety of bonsai pots, we can generally group pots into four categories based on the arrangement of drainage or tie-down holes present.

Below are step-by-step instructions for wiring trees into their pots to keep them securely in place.

One-hole pots

As the name suggests, one-hole pots have a single hole for drainage.

One-hole pot

Because there is only one hole, all tie-down wires will pass through it. As the pot in this example is round, measure the circumference of the pot to determine the length of the tie-down wires. Prepare two wires at this length.

Measuring the tie-down wire

Measuring tie-down wires depends more on the shape of the pot than the number of holes in it, so, for future reference, cut tie-down wires for rounds pots that measure one circumference of the pot.

The next step only apples to one-hole pots. Use a larger gauge wire to create what looks like a cotter pin.

Cotter pin

The straight section of the pin needs to be at least as long as the drainage hole.

Using the drainage hole to determine the size of the cotter pin

The tie-down wires are then wrapped around the pin at least one and a half times.

Tie-down wires secured to the cotter pin

If you carefully feed the ends of the tie-down wires through the mesh of the drainage screen, the prepared pot will look like the pot in the photos below.

Prepared one-hole pot from below

Prepared one-hole pot from above

As it can be hard to see tie-down wires against bonsai soil, I’ll demonstrate securing the rootball with a fabric stand-in.

Fabric “rootball”

To secure the rootball, select two adjacent wires and connect them by twisting the wires.

First two wires secured

Next, connect the other two wires over the rootball and twist the wires until they are secure.

Second wires secured

If there is excess wire, remove it.

Excess wire removed

That’s it for securing bonsai in one-hole pots. This approach isn’t as secure as the following approaches, but it’s the best way to hold a tree in place when only one drainage hole is available.

Two-hole pots

Two-hole pots have two or more holes.

Two-hole pot

Some pots will have a third hole between the two holes shown above, but the tie-down procedure remains the same.

Start by measuring two lengths of tie-down wire equal to the sum of two long sides and one short side of the pot.

Measuring the tie-down wires – two long sides plus one short side

Next, pre-bend the tie-down wires and insert them into the drainage holes, keeping the wires snug against the inside edges to prevent the screen from moving when the wires are tightened.

Bending the tie-down wires

Prepared two-hole pot from below

Prepared two-hole pot from above

Once the rootball is in place, connect the wires in front with a few twists.

The stand-in rootball in place

After connecting the front two wires

After connecting the back two wires

After removing the excess wire

The finished product resembles the finished product of the one-hole pot, but the approach is more secure as there are two anchor points instead of one.

Three-hole pots

Three-hole pots have at least three drainage or tie-down holes.

Three-hole pot with three tie-down holes and one drainage hole

As the pot is round, cut the tie-down wires equal to the circumference of the pot.

Measuring a tie-down wire

Pre-bend the wires so they can connect any two tie-down holes.

Lining up the tie-down wires

Tie-down wires bent

Next, insert the tie-down wires so they connect the drainage holes.

Prepared three-hole pot from below

Prepared three-hole pot from above

The most common question that comes up relating to three-hole pots is which hole gets two wires instead of one. Here’s how to figure this out.

First, determine which side of the pot will be the front. Next, determine if the tree leans to the left or right. If the tree leans to the right, the hole with two wires should be on the right. If the tree leans to the left, the hole with two wires should be on the left. The pot below is wired for a bonsai that leans to the left.

Prepared three-hole pot with rootball

There are two options for connecting the wires in three-hole pots. The first option is to connect each pair of wires in the middle as you did for the two-hole pot.

For added security – especially recommended for cascade or semi-cascade bonsai – connect the wires closer to the holes with one wire each. Here’s what this approach looks like.

First pair of wires connected close to a hole with one wire

Second pair of wires connected close to the other hole with one wire

Taking this approach allows us to connect the tails of each pair of wires to each other for added strength. As this point is the strongest connection, it’s used to counter the weight of cascading branches on the opposite side of the tree.

Connecting the tails

Secured rootball – appropriate for cascade or semi-cascade bonsai that flow to the left

The above tree-hole approach can lead to some confusion when it comes to figuring out which holes should get one or two wires. One way to overcome this is with some practice. Another approach is to repot your tree with a more experienced practitioner. I can add to this a single tip.

If you have a cascade or semi-cascade bonsai, you may find that the tree is tippy after preparing the rootball. If you place one finger on side of the rootball opposite the cascading branch, you’ll find that a single anchor point can keep the tree from falling to the side. This anchor point is where you want the final tie.

Four-hole pots

Four-hole pots have drainage or tie-down holes in each corner of the pot. There may be additional holes in other locations.

Four-hole pot

As the pot is a rectangle, measure the tie-down wires equal to the length of two long sides of the pot and one short side.

Measuring a tie-down wire

At this point, there are a couple of options. The simple option is to follow a modified version of the two-hole approach that uses the corner holes instead of the drainage holes in the middle of the pot. This approach can be good for trees with solid rootballs.

A second approach has a few more steps, but provides a more secure connection. Here are the steps for the more secure approach.

When pre-bending the tie-down wires, make one side longer than the other.

Tie-down wires bent as seen from the left-hand side of the pot

When inserting the tie-down wires in the corner drainage holes, connect the holes on the left with one wire and the holes on the right with the other wire.

Prepared pot from above

Prepared pot from below

Which holes get the longer sections of wire? Like the three-hole approach, this bit depends on which way the tree leans.

  • If the tree has strong movement to the right, place the longer sections of wire in the front left and back right holes.
  • If the tree has strong movement to the left, place the longer sections of wire in the front right and back right left holes.
  • If the tree doesn’t have strong movement in either direction, either of the above approaches will work.

Prepared pot with rootball

For this example, we’ll assume the tree leans to the right. First, prepare a short section of wire with a loop on one end.

Short section of wire with loop

Insert the front left wire into the loop. We’ll use this “tail” for the final tie.

The tail affixed to the front left wire

Bring the front left wire across the rootball to the front right drainage hole and connect the wires with at least three twists. The twists can be done with pliers or fingers.

Covering the rootball with the first tie-down wire

The first connection

Next, bring the front right wire across the rootball to the back right corner.

Covering the right side of the rootball

Connect these wires with a few twists. Next, bring the back right wire across the rootball towards the back left corner.

Covering the back side of the rootball

Connect the wires.

Back left wires connected

This is where the tail comes in. For the final tie, connect the tail in the front left corner with the wire in the back left corner.

Connecting the back left and front left wires

This final connection should be tightened with pliers. Remember to pull first, then twist when tightening the connection.

The final tie

Rootball secured

Like the three-hole approach, this approach may take some getting used to. Practicing with a block of wood or getting 1-1 instruction during a workshop can help. With enough repetition, this approach can become natural.

Some common questions about the four-hole approach:

  • Does it matter if I connect the wires counter-clockwise as in the example or clockwise? Not really. If proceeding clockwise, however, the longer sections of tie-down wires will need to be reversed (for trees that lean to the right, place the long sections in the top left and bottom right holes and start with the front right wire).
  • Does it matter if I start in the front or the back of the tree? Only if the tree has a strong lean. As the final tie is the strongest anchor point, try to arrange the wires so the final tie is on the side opposite the part of the tree that leans.

General questions about securing bonsai in the pot:

  • I’ve seen videos where bamboo stakes are driven into the rootball and the tie-down wires simply hold the stakes in place. Does this approach work well? The bamboo stake variation can work great when the rootball is solid, and it uses less wire. It doesn’t work as well if the rootball is loose.
  • Should I use copper wire, aluminum wire or steel wire for tie-downs? Any wire that doesn’t erode quickly will work. I usually use aluminum wire as it’s less expensive than copper wire and it’s easy to work with.
  • What size wire should I use for the tie-downs? This depends on the size of the tree and how strong a lean the tree has. I use 1.5mm or 2mm aluminum for most trees and 2.5mm or 3mm – or stainless steel wire – for the largest trees.

Would you like to see some examples using real trees? Here are step-by-step shots of the process with a trident maple, with a young black pine, and with a Sawara cypress. These articles, particularly the trident maple article, will also provide an overview of the basic repotting process.

Next up: Part 8 – how to wire a Y

Repotting a trident maple bonsai

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Several years ago, I published a series on how to repot bonsai. For those who missed it the first time, here is an edited version of the series in a single post. Enjoy!

How to Remove a Bonsai Tree from the Pot

Before a bonsai can be moved into a new pot, it must be removed from its current pot. Here’s a trident maple bonsai before repotting.

Root-over-rock trident maple

The first step is to remove all wires that poke through the bottom of the pot. I usually begin with the tie-down wires and then remove the clips that hold the drainage screen in place.

Tie-downs cut

Cutting the clips

I’m always sure to remove all of the wires as a single remaining wire can help a tree cling to its pot with surprising tenacity. Once the wires are removed, I set the pot back down and get out the sickle.

Wires removed – ready for the next step

Using a small sickle or a sod-knife, I carve a narrow trough between the rootball and the sides of the pot. This is the most dangerous part of the process. While one hand holds the pot in place, the other works quickly with a sharp implement. Watch out for your fingers!

Separating the rootball from the sides of the pot with a sickle

I’ve found that a smooth, scraping motion works better than vigorous jerking or saw-like motions. How much scraping you do depends on the tree and the pot. Since the idea is to disturb the roots as little as possible at this point, it’s important to do no more scraping than necessary. That said, trying to remove a tree before the roots are free can damage roots.

For square, rectangular, and oval pots, work on the two short sides of the pot and one large side. Trees usually release from round pots after about half of the diameter has been cleared. In all cases, scrape to the very bottom of the pot. Because roots tend to circle at the bottom, stopping short of this mass can prevent the tree from coming out.

Soil cleared

Once the soil has been cleared down to the bottom, it’s time to remove the tree from the pot.

This step requires care. Try to keep the pot on the workspace while tipping the tree away from the pot by raising the end of the rootball that has been cleared with the sickle. Dangers at this stage include crushing branches and flicking pots to the floor.

Tilting the rootball away from the pot

While this procedure may seem a bit formal, the idea is to avoid common pitfalls.

Preparing the Pot

The next step is preparing the pot into which the bonsai will be planted. This year I’m repotting the trident maple back into the same pot. I usually go out of my way to make a change when I repot, but it’s OK to reuse the same pot too.

It’s best to prepare the new pot before working on the roots. Preparing the pot involves scrubbing, covering the drainage holes with screen, and wiring the pot.

Grimy pot

I like to use a natural-bristle brush, but plastic brushes work well too. What’s important is the extent to which you clean.

I cannot overstate the importance of this next bit: do not be over zealous in your scrubbing! It’s easy to remove both grime and patina when scrubbing, though the goal is to remove the grime while preserving the patina.

Scrubbing away soil residue

How much to scrub? A good way to start is to scrub lightly. This will remove most of the crust or loose dirt that can cling to pots. Beyond that, proceed with care. Some white residue from hard water is acceptable, too much is not. Green colored build-up is rarely appropriate. If you ever have a question about cleaning a specific pot, don’t hesitate to take it to someone you trust for advice. It’s not worth the risk and it could save you some effort.

Once the pot is relatively clean, it’s time to cover the drainage holes. The process is simple once you know how to do it. Measure a piece of wire about four times the diameter of the drainage hole. Bend the wire into a “z” shape with your hands and finish the bends with a pliers. From there, bend down the ends so they just fit inside the drainage holes. A good fit will prevent the screen from moving around. This helps keep soil in and bugs out.

Measuring wire for the clip

Starting a clip

Checking the size of the clip

A completed “clip”

After the screen is in place, measure the tie-down wire. For rectangular and oval-shaped pots, get the length of the tie-down wire right by measuring two long sides and one short side of the pot as a guide. Differing shapes and drainage hole arrangements necessitate adjustments. Getting the length right becomes easier with practice.

Measuring the tie-down wire

There are a number of techniques for securing trees in bonsai pots. Each method entails a certain arrangement of the tie-down wires. For the method I’ll be using with this trident maple, I arrange the wires as follows:

From below

From above

Once the wires are in place, I bend them out of the way and set the pot aside until I’m ready to set the tree.

Why bother with wires at all? It’s a reflection of the difference between a nursery trees and bonsai. Bonsai typically require more care. Holding the roots in place while they grow into their new environment minimizes the damage that can result from jostling a tree around. It keeps expensive trees from blowing out of their pots and tippy trees from falling over. It’s a sign that we really care about the well-being of our trees.

Root Work

Great bonsai work requires great tree health, and great tree health begins with the roots.

Cutting too many roots can weaken or kill a tree – not cutting enough can lead to root rot or dieback and prevent good surface roots from developing. When done well, however, repotting can invigorate bonsai and give them the strength to recover from the most intensive styling techniques.

Trident maple is best repotted in late winter or early spring. And while most deciduous trees are typically repotted before they leaf out, tridents can be repotted as long as the new leaves are reddish in color. Repotting this late can slow a tree down a bit, but if it’s in otherwise good health, it won’t skip a beat.

Root-work begins, in this case, with the bottom of the rootball. After removing the tree from the pot, I can see that the roots are loose where the sickle passed, but nice and compact on the other side. Tipping the tree onto the untouched side can protect the rootball while I work on the base.

Rootball – where the sickle passed

Rootball – the untouched side

I’m fairly picky about the tools I use when I repot. I’ve found that the rake below is perfect for combing out the roots on the bottom of the rootball. I work from the center and drag the rake outward while keeping it parallel with the base of the tree.

Raking the base of the rootball

I try to keep the base as flat as possible when I work to avoid causing air pockets when I set the tree in the pot. Holding the rake at an angle or working for too long in a single area can quickly create pockets, and in some cases, can weaken the entire rootball.

Working on small trees planted in good soil is fun work

Cutting roots flush with the soil can make it hard for the roots to grow into new soil. By leaving a little root sticking out from the rootball when I cut, I can help the roots integrate into the new soil.

Root-work completed on the bottom of the rootball

Once the base is done, I can set the tree down and work on the top and sides of the roots. Bent-nose tweezers are great for this. I’m careful, however, not to hold the tweezers too high when I work. Holding tweezers at steep angles can snag roots, causing them to snap or tear. By holding tweezers at a lower angle, I can help the tips glide over roots without damaging them.

Improper tweezer technique (angle too high)

Better tweezer technique (appropriate angle)

You may have noticed that the soil is darkest near the surface of the roots. That’s evidence of the organic fertilizer I use – cottonseed meal, in this case. To improve the drainage, I scrape away as much of it as possible. When I’m done, I cut the roots just past where they come out of the soil.

Root-work completed

Securing the Tree in the Pot

Once the tree and pot are ready, it’s time to put them together. For starters, the pot gets a drainage layer of pumice. If the pot were much thinner or the climate warmer I might skip this step, but I’ve found my trident maples do well with a pumice drainage layer.

Pumice drainage layer

After spreading out the drainage layer, I add my deciduous bonsai mix – mostly akadama with pumice, lava and charcoal. I typically form a mound in the center of the pot when I pour in the mix to help prevent air pockets from forming when the tree is set. If the base of the rootball is concave, this is important.

Mound of bonsai soil

Next comes one of the most important parts of the whole process – setting the tree. Although it’s not a very technical maneuver, it requires care to make sure the tree ends up in the right spot. After nestling the tree into place, check the location of the tree, the height of the rootball, the tilt of the tree, and the front. Make any adjustments, if necessary, before securing the tree into place with wire.

Setting the tree

There are many ways to secure a bonsai in a pot. The goal is to prevent the tree from moving to avoid damaging new roots.

Before I attach the first two wires to each other, I add a “tail” – an extra piece of wire that will help me make my final connection as I work my way around the rootball.

Adding a “tail”

I then pull the first wire to a location above the spot where the second wire comes through the drainage hole. I make a few twists by hand and continue around the tree until it’s time to connect the final wire with the “tail” I attached to the first wire. This final connection requires pliers.

Securing the tree

A subtle but important trick to using pliers: pull, then twist. If you’ve repotted at Boon’s, you’ve heard the phrase before. The idea is to pull the wires taught, then slightly release the pressure as you make the twist. Doing this helps one avoid breaking the wire.

Proper plier technique: pull

Then twist

When done well, using the pliers for the final connection tightens all of the other wires. It’s a fast and effective way to secure a tree.

Tree secured

Before adding more soil, I trim any extraneous wire.

Finishing Touches

The hard part is over. The next step is to add more soil to the pot.

Pouring the soil with a scoop

When working the new soil into the roots, chopsticks come in handy. I usually jab lightly at the soil with one hand while holding the pot and soil in place with the other. Skipping this step can result in air pockets that make it tough for the roots to take hold.

It’s fun, at this stage, to wiggle the chopsticks about. Wiggling really works the soil into place and is especially effective at filling pockets between large roots or cavities beneath the trunk. Over-wiggling, however, is counter-productive. Unless there is a big gap to fill, it doesn’t take much.

Working the soil between the roots with chopsticks.

Before getting a final level on the amount of soil in the pot, a careful bump can settle things a bit. When doing this, I very carefully hold the tree and pot in place with one hand while bumping – just once or twice – with the other. Careless bumping can upset the soil and occasion a do-over. If the soil drops dramatically, it’s a sign that I didn’t use chopsticks enough to work the soil into place.

Bumping the pot

A small brush can help get the soil to the proper level. Of brush-technique: holding the brush at a high angle makes it hard to level the surface of the soil and can easily gouge out additional soil. Holding it close to parallel to the surface of the soil pulls the largest soil particles out of the mix and makes for a nice level.

Leveling the soil in the pot – improper brush-technique

Proper brush-technique – the brush is nearly parallel with the surface of the soil

A trowel can make the surface neat and tidy. I’ve seen long trowels and short trowels, custom trowels and mass productions. I have two, but I rarely use them. I like patting the surface of the soil with my hands instead. It works almost as well and is much faster.

Tamping the soil with a trowel

Tamping the soil with my fingers

As soon as this is done I go outside and water the tree. The rule about watering until the water runs clear is sound. The more dust particles you can wash from the soil, the better the soil will drain. It’s at this point that I gauge the effectiveness of the work. If the drainage is poor after repotting, I need to start over.

Watering the tree

The tree is now set for the coming year.

Repotting complete

The above covers many of the repotting basics. But as with so many bonsai techniques, there is a lot more to say on the topic. If you still have questions about how and when to repot, don’t hesitate to ask someone with experience growing bonsai in your area – it’ll be worth it!

Pot selection – exposed root black pine

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One of my favorite activities relating to bonsai display is pot selection. I’ll be showing a young black pine at tomorrow’s Bay Island Bonsai exhibit and the pot used for the past year isn’t exactly show quality.

13 year-old black pine in colander

Here are 11 options for the tree. Some look great to me, others less so. A couple of my favorites are either a bit too small or a bit too large. Any favorite combinations?

Pot 1 – scalloped sides

Pot 2 – Chinese antique

Pot 3 – nanban style

Pot 4a – Reiho

Pot 4b – same pot from the other side

Pot 5 – drum pot

Pot 6 – shallow dish

Pot 7 – nanban

Pot 8 – flower-shaped pot

Pot 9 – square pot

Pot 10 – Bunzan

Pot 11 – square pot

To see the final selection, come to Bay Island Bonsai’s 17th annual exhibit this weekend or stay tuned for upcoming posts from the exhibit.

Repotting black pine in nursery soil

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Sometimes during repotting, I feel like I’ve passed a point of no return. The feeling struck when I was working on a black pine this past winter.

Repotting black pine

After combing out the roots – there’s no going back

The pine – see Friday’s “Cleaning up a black pine” for a look at the tree today – is undergoing the transition from landscape material to bonsai. One of the more radical aspects of the transition happens in the pot – the switch from nursery soil to bonsai soil.

The first time I repotted the tree, I had to remove a lot of roots to get it into a smaller pot. This didn’t provide a good opportunity to change out much old soil as I wanted to keep the tree strong. Two years later, the tree was strong enough for a more invasive repotting so I went about bare-rooting half of the rootball.

Bare-rooting bonsai typically reduces vigor greatly and it can kill conifers. For this reason, it’s common practice to bare-root a portion of the rootball – maybe 1/3 or 1/2 of the rootball – one year and bare-root another portion in a subsequent repotting 1-2 years later. That’s the approach I took with this black pine. Here’s the tree before repotting.

Black pine

Before repotting

After removing the tree from the pot, I had to decide which side to bare-root. I selected the side with the least amount of roots. This reduced the stress to the tree – I could preserve more fine roots this way – and it left me with a solid chunk of soil that would help me anchor the tree in the pot.

When bare-rooting, I try to remove old soil without damaging the roots. This involves carefully combing out the roots with root hooks and chopsticks – a labor-intensive process. Depending on the condition of the old soil, I’ll sometimes rinse off the bare-rooted half of the rootball with water to completely remove the old soil.

Repotting black pine

The bare-rooted half of the rootball

Repotting black pine

The intact half of the rootball

Repotting black pine

Half-bare rooted rootball from above

When the rootwork is complete, I take care to ensure the intact part of the rootball stays together. After adding a drainage layer to the pot, I nestle the tree into place and make sure it’s centered and positioned at the right height. Once the tree is set, I begin adding soil.

Repotting black pine

After setting the tree

I used a chopstick to prop up a root that was growing downward. In this new position, it can form part of the surface roots.

Typically, the next step is wiring the tree into the pot. When working with exposed roots, however, I work in soil between the roots before wiring the tree into place to avoid crushing the roots.

Repotting black pine

After adding some soil between the roots

Repotting black pine

After adding more new soil – just a bit more to go

When the soil has covered the roots, I can wire the tree into place like I normally would.

If the tree is wobbly after wiring the rootball to the pot, I’ll add a prop or a guy line to help hold the trunk in place. The roots and intact portion of the rootball provided a good anchor for this tree so wire sufficed.

Black pine

After repotting

I began fertilizing the tree a few weeks after repotting and am now feeding heavily in anticipation of decandling later this spring. I’ll think about removing the rest of the old soil in a year or two depending on how the tree grows in the meantime.