Bonsai Basics is a NEW blog series dedicated to providing beginner’s tips, tool recommendations and facts about basic bonsai tasks.
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Photo Credit: Bonsai Empire
There’s the holiday season, spring cleaning season and back-to-school season – but as a bonsai beginner, there’s one season you should really familiarize yourself with: repotting season.
You might have a lot of questions about when to repot, what to use to repot and how repotting works. We spoke with NBF Co-President Felix Laughlin about the basic tools and steps you need to get your repotting off to a great start this spring.
“We’re at the critical point where most bonsai are about to leaf out if they haven’t already,” Laughlin said. “This is when the bonsai are the healthiest for repotting and cutting back roots.”
He said younger bonsai should be repotted each year, but more developed trees can wait longer.
“Repotting is like renewing the life of the tree and giving it a chance to live a lot longer than it would growing in the ground,” Laughlin said. “That’s why you have 1,000 year bonsai – repotting helps bonsai roots not wrap around the pot, get old and stop feeding the tree.”
How to Tackle Repotting
An eight-piece tool kit featuring the snips, three-pronged ranks, sickle and pliers discussed below. Available on bonsaioutlet.com for $69.95.
The first step to repotting your bonsai is cutting the wires tying the tree into the pot. Grab your root hook and transplanting sickle or scythe – a curved, sharp saw or cutting edge – and saw or cut around the edge of the pot to remove the root ball without tearing it apart.
Then use a three-pronged root rake to scrape the bottom of the root ball, removing soil and exposing the downward-growing roots. For root balls removed from deep pots, you may first need to use the curved sickle or a saw to cut off the bottom portion of the root ball.
Next you’ll want to use some scissors or hand snips to cut back the exposed roots, including those growing laterally around the sides of the root ball. You might use bent-nose tweezers and a root hook to help untangle the roots.
This seven-piece tool kit includes: root cutters, root rake, sickle, angled scissors, broom, bent-nose tweezers and root hook. Available on bonsaitonight.com.for $135.
But pay attention to which kind of bonsai you’re working on. Laughlin advises that the roots of deciduous bonsai can be cut back harder than those of evergreen bonsai.
“It’s a balancing act,” Laughlin said. “You want to rejuvenate the roots without diminishing the ability of the tree to recover.”
Next, place some fresh soil into your pot and tie the tree back in with wire, pliers and wire cutters. Laughlin said any pair of pliers from a hardware store will work, but some technical bonsai pliers offer more precision – though they cost more.
Watch bonsai master Boon Manakitivipart as he demonstrates some of these repotting steps and illustrates the use of the repotting tools.
Sickles, three-pronged root rakes and root hooks generally each sell for around $10. Laughlin likes the Okatsune heavy-duty hand snips, which can be found at Bonsai Outlet for $40.
“They’re top-notch Japanese shears that are great for cutting heavy roots and getting the root ball back down to where you want it,” Laughlin said.
Bonsai tools can rack up a lengthy bill, but Laughlin said you can cap your costs at about $100 if you do your research. He said not many brick and mortars offer kits with all the tools he discussed, but you can find reasonably priced starter sets or individual tools on sites like Amazon, Bonsai Tonight, Bonsai Learning Center, Stone Lantern, Bonsai Outlet and Brussel's Bonsai.
When Should You Start Repotting?
NBF Co-President Jack Sustic works with NBF board member Dr. Joe Gutierrez to repot a bonsai.
NBF Co-President Jack Sustic said you’ll want to repot deciduous trees first, which grow more vigorously and sooner than conifers, which are generally ready for repotting in late April.
Sustic said the repotting season can change depending on where you live – someone in South Carolina might be done with repotting for the year but someone in Michigan could just be getting started. Sustic says to start repotting once buds have started to swell up and gain a bit of color.
For Sustic, the frequency of repotting depends on the tree itself. Your bonsai likely needs repotting if water sits on the soil and doesn’t drain well or if the overall health of the tree is poor.
“I look at it from a horticulture standpoint,” Sustic said. “Questions like, ‘Is the tree healthy, is it growing, is the soil draining well?’ Ultimately, the tree will tell you when it’s ready to be repotted.”
Check out our Youtube page for a demonstration by Danny Coffey repotting a boulevard cypress.