What would YOU do if you took your new azaleas out of the pot and discovered a mess like the ones I bought last week at Home Depot? I tried slicing through the mass to loosen the roots, but didn’t get far. Do my two ‘Girard’s Renee Michelle’ azaleas have a chance at survival?
No shortage of advice
For answers, I posted this photo to the DC Gardeners Facebook group, where I was happy to learn that “Home Depot will refund anything, even plants that are brown because the customer never got around to planting them.” Who knew?
I asked the group where I could buy plants that aren’t totally root-bound and discovered lots of fans of various garden centers in the area, as well as predictions that these badly grown plants could be found in any retail establishment. (This was confirmed by a very knowledgeable garden center expert I’d known for decades, who told me the growers are saving money by reducing or eliminating the actual growing medium in the pots, using instead fillers that simply cause the roots to dry out. Also good to know, though discouraging to hear.)
For the azaleas I’d already bought, the group told me to use “root washing or just slicing, shaking and spreading the roots apart carefully.” The standard advice.
I also asked the Garden Professors Blog Facebook group where several commenters told me to do what I’d already tried doing: some version of “Tickle out all the roots.” But believe me, this concrete-like mass was NOT to be tickled with.
Or “Don’t tug or yank just literally tickle and you will slowly feel all that particular matter falling away. I use a big wheelbarrow. I sit down next to it and then I just spend at least an hour doing that.” Did you catch that – an hour of “tickling” per shrub?
Honestly, I think this response from a group admin nailed it: “Personally I’d prepare this one by taking it back to the garden center and either getting a replacement or get my money back.”
But others, including admins, directed me to the root-washing and -pruning that I’d seen promoted so many times in the group. Now they’re telling me it applies to this azalea of mine? I guess it’s time for me to step up and give it a try.
The one video posted to the group unfortunately showed nothing but the backs of people watching someone perform a very brutal-looking root-pruning, so I just googled “root pruning” and found some goodies:
- Jeff Gillman on “A better fix for root-bound plants,” which included the new-to-me technique of “box-cutting.”
- And some good information about planting pot-bound plants from U. Florida.
Dave Marciniak demonstrates root-washing and -pruning.
I learn best by watching, so my favorite discovery was this video by Dave Marciniak, owner of Revolutionary Gardens in Northern Va. He also lists some resources, where I found this slide show by Dr. Linda Chalker-Scott, which he calls a “bare-root primer.” The slides below particularly inspired me – and then discouraged me, since there was NO way I could accomplish “media removal” with my new azaleas.
Watch me try, and not get very far
To watch click here or anywhere in the image.
Above, an azalea soaking in water for hours; the sliced-off bottom of a root ball; the resulting root ball after about 25 minutes of hacking away at it.
What about the azaleas I planted in 2023?
Next, I turned to the two azaleas of the same type that I’d planted in 2023, now that I’m willing to admit that they look like crap. Above, note the difference between the brand-new ‘Girard’s Renee Michelle’ on the left and the one I planted two years ago that hadn’t grown at all and has sparse, sickly-looking foliage. I bought it at a large and reputable (I guess) garden center.
So I dug them up (too easily) and discovered the same damn problem, plus evidence of something predicted by a Garden Professor commenter: “Also you should expect that it’s been potted up at least once. When you remove the outside matted mess you’ll find what’s basically another interior layer from maybe a 6” pot where it was rootbound previously before being potted up.” Another commenter agreed: “Great point! Lately I found plastic foamy liners that were never removed but just potted up. It’s like digging for treasure in the center of the rootballs.”
I removed one two-inch thick layer of roots, which revealed another layer, then the innermost layer, which was concrete-like.
Shrubs grown and potted-up correctly – my new ‘Wine and Roses’ weigelas
After hours of hard labor trying to correct four badly grown azaleas, I decided to give up and give myself permission to give them away and try something entirely new in this spot – a spring flowering shrub that did very well in my former garden, where I grew an assortment of large flowering shrubs that grew quickly and naturally had good form – especially weigela. For my current townhouse garden I chose the medium-size ‘Wine and Roses’ with it distinctive dark foliage that would contrast nicely with all the azaleas in my neighbor’s half of our adjoining border.
At the nursery (NOT the one that sold me the bad azaleas two years ago) a staffer was happy to pop them out of their pots so I could see the roots – and they were perfect!
See, it took less than a minute to prepare them for planting.
To watch, click here or anywhere in the image above. At planting I spread the longer roots out, away from the center.
Above left, the finished rootball ready for planting. The “growing media” fell away with a bit of “tickling,” just like everyone predicted because they’d been grown and potted up correctly.
Here they are newly planted, ready to bloom soon and contrasting nicely with a ‘Lucky Devil’ ninebark. In the foreground is some groundcover comfrey, already blooming and covered with bees.
Fortunately my next-door neighbors had room for my new azaleas, so I’ll be able to enjoy them from my garden and report on their survival, or their demise.
Videos by the author, using my favorite tripod.
I suspect all the energy you spend messing with the root ball may have cause the poor performance of the azaleas. If you had simple scored/sawed the dense root masses at the outer edge of the pot, the roots would travel into the soil you inserted into the hole you dug out. We know if you fill the hole with super loose nutrient rich potting soil, then the plant won’t be encouraged to acclimate to the natural soil of the land where you are planting it. Only a bit of nutrients added to the natural soil is the best way to encourage outward root growth.
The DC azalea society sale is April 26 at Meadowlark Gardens (Vienna VA). The azaleas should not be root bound. Meet hybridizers who have culled well rooted shrubs
This is an interesting one.
The level to which a plant can be rootbound varies enormously between genera and sometimes even from species to species. Some plants, such as Embothrium and Drimys for example, are potbound pretty much as soon as they reach the edge of the container. Others, like Rhododendrons, make very fibrous root systems that usually look more rootbound than they are.
I’ve never teased root systems of plants. During my nursery days we were potting ~80,000 young plants a year, some of which were definitely pinched in their pots before potting. We didn’t have time to fiddle with them, but also never had issues with them rooting.
If you need to do anything to roots then it’s better for the plant if you do major surgery rather than teasing roots out. Cutting the lower third of a root system away will put the plant into shock and it will make lots of healthy new roots… usually. Some plants, like Rhododendrons, are a bit less inclined to respond well.
Much of the success of establishment depends on the nuances of soil and maintenance, but removing a large amount of an azalea’s root system will make that challenging as the root system is so heavily compromised. For what it’s worth I think your Home Depot azalea would probably have been fine just planted whole and watered well. Roots are eminently able to push into the soil without intervention; I hold that a lot of the ‘you must do this and that’ advice is outdated and needs challenging.
I have had great success following the garden professors recommendations re root prep. For example I purchased a Japanese maple for a great price that was a root bound disaster, as bad as the azalea pictures. It took way over an hour of root washing, with pruners and a garden claw. I wasn’t able to.”tickle” the roots, rather treated it more like a slasher movie. My landscapers were there at the time and were pretty shocked. But it looks absolutely amazing now. Most of the plants the landscapers installed using common planting procedure have rootballs that are mostly still intact years later when removed. I also do not add amendments to the soil as per the garden professors recommendations. Their advice is counter to what I was taught and practiced for decades, but has yielded great results. It can be time-consuming and impractical for commercial landscapers, but the idea of loosening the roots of properly potted specimen is not difficult. Happy gardening!
The three shrubs I root washed, variegated Diervilla, have never thrived. I now only purchase small shrubs, mostly in 4” pots from Bluestone Perennials. I pot them when I receive them in April, and upsize them a couple of times over the summer. By fall they are ready for planting out, and they thrive.
Susan, as a nursery professional for over 30 years and a landscape contractor for over 15 before that I can assure you that root bound plants are just part of the challenge of production. Like Ben mentioned above, some species are notorious for this condition. Azaleas and heather (both Ericaceous) have a fine matrix of roots that quickly mass together and are nearly impossible to tease apart. As an installer and grower, I personally like to use a good old fashion linoleum knife to score the edges of the root ball. I am also a big fan of slicing off the bottom inch of the root ball. Make sure to sharpen the knife from time to time. Ornamental grasses are another group that become root bound quickly. As Ben also mentioned, soil prep is just as important as root pruning. There are two schools of thought when it comes to soil amendments. Bareroot plants don’t generally need any amendments and neither do Balled and Burlaped ones which have their own challenges due to the dense clay balls that can quickly dry out and are then impossible to rehydrate. But for container grown plants like your azaleas that are grown in a soilless mix I firmly believe that creating a transitional soil with amendments helps facilitate the movement of water and air and encourages better rooting. Finally, proper “watering in” is what will make or break a successful transplanting operation. Hope this helps. Steve
It sure does help. Thank you!!
Garden Rant needs more of these practical gardening discussions which are far more useful than the “Native Plant Elitists vs the horticulture trade” or “lawns vs meadows” controversies.
Hear, hear!
Susan, you certainly got a lot of “advice”! I started root washing using to Linda Chalker-Scott’s method over ten years ago. Working at Behnke Nurseries showed me a lot of temptation. Most notable were three Kentucky Coffee trees that had been on the nursery grounds for at least three years. Though in 10-gallon pots, they were not only “elite” plants, but seriously root bound. They each took several hours of washing and untangling. That was five years ago. They never looked back. I can give you many such stories – examples from my own garden as well as client’s gardens. You did not spend nearly enough time on the azalea in your video. Plants similarly root bound take hours, both soaking and using a much stronger spray than you illustrated, to detangle. BTW, I have yet to cut off the bottom of the root mass.
Scanning the headline, I read read foot-washing or foot pruning my horribly foot bound…..what? ? Horrible visions floated across my mind….. Relieved it was only azaleas!
I never buy a plant without removing the pot and looking at the roots first. Big boxes especially are just as bad about selling poorly rooted plants with heavy top growth and overwatered plants with rotted roots. I guess that still won’t prevent buying something grown from pot bound liners, though. And should a garden center ever object (which hasn’t happened) then I wouldn’t want to shop there, anyway.
As a former garden center owner, it was not uncommon for me to remove a plant from its pot to show the customer what they would be dealing with. Their success was always top priority.
Good mornings! I’m curious as to what Continued Care is provided to the soil health for your long lifespan plants after you have planted? Do you continue to feed the soil biology beyond the planting hole to encourage the roots to push out of the hole? Do you aerate the soil between plants as needed? Roots can do the same ‘packed’ growth in “untended” soils where shrubs/trees/etc are planted, mulched, watered, trimmed….. but the soil is ignored. It takes deciduous plants 3-5 years to settle in, evergreens 5-7 years. The soil health and water needs should be monitored during this time….. and after for plants not native to your yard.
there is so much to learn about plants and root systems in a pot and knowledge what to do me as a grower for over 55 years some experience in growing plants ????
travel for more than 35 years and visit and talk with so many growers in the fields was shy in the beginning to talk about the difference in growing plants in pots in Europe or the US ,SOILMIX is Very Important the time that the plants has been on the fields by the grower and is it 1 season or 2 or 3 years
do not want to go to far in details but we can learn always
What an interesting article about a subject all of us have faced. I have never taken the time to “tease out the roots” of a potbound plant. Instead, I either break apart the mass with my hands (if it’s coming from a smaller pot), cut into the mess in a couple of directions with a knife, or lay the plant down and stab through it a time or two with a shovel. I am of the “put nice soil into the planting hole” team. I then water in well. In my many years of gardening, this has always worked for me. I am anything but lazy; however, I am all for accomplishing a task in as short a time possible, leaving me extra time for other gardening chores.