Grower's guide
Why root-pruning grow bags grow better plants
How fabric containers prune roots, what research has found, and why nurseries, tree farms and growers have relied on them for more than 40 years.
The problem with smooth plastic pots
When a root reaches the smooth wall of a plastic pot, it doesn't stop. It turns, follows the wall and keeps circling for as long as the plant stays in the pot. Over time those roots harden in place, and they don't straighten out after planting.
Container-grown nursery stock is prone to circling roots, including ones hidden inside the root ball. Left alone, circling roots can turn into girdling roots that wrap the trunk and restrict the flow of water and nutrients. Warning signs include early leaf drop, small leaves and canopy dieback.
How air pruning works
A fabric container lets air through its walls. When a root tip grows into the fabric and meets dry air, the tip dries out and stops growing. The plant answers by pushing out new branch roots further back along that root.
Repeat that across the whole root zone and you get a dense, fibrous root system that fills the container, instead of a few long roots wrapped around the outside.
The fabric itself makes the difference. How it is made decides how much air reaches the root tips, how quickly the root zone dries and how many seasons the bag holds up. RootPro founder Matt came to grow bags from a textile manufacturing background, and the fabric in every RootPro bag is the result of years of experimenting with that balance.
What the research shows
Five reasons growers switch to fabric
Fewer circling roots
Typically five times less root deflection and circling in fabric containers than in traditional pots.
Cooler root zones
Our grow bags are grey and breathable, they don't attract heat from the sun and airflow keeps roots cool.
Bigger trees in the nursery
Caliper, height, leaf area and root ball quality are significantly greater in fabric containers than in traditional pots as soon as the second nursery season.
Roots that move out after planting
Pruned roots jump after transplant. You can expect faster root growth and less shock after planting
More roots at harvest
Digging a field tree with a tree spade removes about 90% of its root system. Fabric grow bags retain the entire root ball.
Who uses root-pruning containers
Wholesale nurseries use fabric pots from the propagation to container yard to produce liners and finished stock with fibrous, non-circling roots.
Tree farms grow in in-ground fabric bags and lift the whole bag at harvest, saving time and labour and keeping more of the roots with the tree. Large above-ground bags hold caliper trees in the yard.
Container berry and vegetable growers use them for drainage, aeration and cooler roots in full sun.
Landscape and municipal planting crews get trees with fewer circling roots to correct at planting time.
What to plan for
Fabric breathes, so it also dries out faster. Plan for drip irrigation or a regular watering schedule.
In-ground fabric bags must be removed at planting so they don't restrict future growth.
The advantage of fabric is the root system you grow and sell: fewer circling roots, more fine roots, and a root ball that's ready to grow out.
Questions
Root pruning FAQ
Do fabric grow bags really stop circling roots?
They greatly reduce it. Roots that reach the fabric are air-pruned and branch instead of circling. Typically about five times less root circling in fabric grow bags than in plastic.
Do fabric pots need more water?
Usually, yes. Air and water vapour pass through the walls, so fabric dries faster than plastic. Most growers use drip irrigation or a regular schedule.
Can I reuse fabric grow bags?
Yes. Either keep outside full with soil or empty them at the end of the season, rinse, let them dry and fold them flat for storage.
What size should I use?
Check the size guide on our Fabric Grow Bags page, or send us what you're growing and we'll recommend a size.
Do you supply nurseries and tree farms?
Yes. RootPro sells online and in bulk. We supply 5-Packs to truck loads! With over 100,000 units in stock.
Why buy from RootPro
The easiest way for Canadian growers to buy grow bags
Ordering from a U.S. or overseas supplier can mean border crossings, exchange rates and fees you only see at the door. RootPro takes all of that out.
No cross-border shipping
Your order ships from London, Ontario. So there's no border crossing to wait on and no customs paperwork to fill out.
No duties or brokerage fees
No surprise brokerage and duty charges when the box arrives. The price at checkout is the price you pay.
Priced in Canadian dollars
No exchange rate to guess at and no foreign transaction fees on your card.
Simple ordering
Pick a size, pick a pack, and check out. Buying nursery volumes? Request a quote and get one price back.
Talk to the owner
Questions about sizing or volume go straight to the owner:
519-870-8923 or mclarke@rootpro.ca.
Every size in one place
Fabric grow bags from 2 to 100 gallon, plus geotextile for the rest of your operation, from one Canadian supplier.
Shop RootPro grow bags
Air-pruning fabric grow bags from 2 to 100 gallons, in 5, 20 and 50-packs. Bigger packs lower the price tag.
Ready to grow better roots?
RootPro fabric grow bags air-prune roots with a fabric developed and refined over years of testing. Order online in packs of 5, 20 or 50, or request wholesale pricing for nursery and farm volumes.