Nursery Notes: Container liners can offer problems
I think the advantages of fall planting outweigh all other seasons. I regret more bareroot liners are not available for fall planting. I was extremely pleased when our producers started buying potted liners and planting them in the fall. I think it is wonderful that several of our area liner producers are now growing potted liners to meet the local demand.
Containerized liners are great, but their shelf life is more limited than many in the industry realize. There is nothing wrong with starting a seedling in a cone or tree band. There is nothing wrong with sticking cuttings in 2 or 3 inch pots.
It is a sin to hold plants in containers to long. Plants should not be started in small containers in the early spring and then shipped that fall in the same container.
Root systems will fill these small containers in a matter of weeks. Kinking and circling is the result.
The plants must be stepped up into a larger container to avoid roots from kinking and growing in a circle. When a full season is not required for a root system to fill a container, then it should be started later, closer to the selling date.
The problems generated by root bound root systems is receiving national attention. Workshops are being conducted where the surface root systems are exposed, then dug with a backhoe, and then dissected. When the root system is split down the center, top to bottom; the various container sizes that it once grew in are very apparent.
A quality container liner can not be held in a container too small for the growth. Circling roots can not be allowed to grow more than a few inches before they are removed and stepped up. Standards are being written.
So, your market is to grow and sell 3 gallon liners, not 5’s. But your customers do not want a 5 gallon. Pretty soon they will not want circling roots. We may have to start the crop later or learn to push them less. I prefer a 5 foot branched tree liner over a 7 foot unbranched that can not support it’s own head.
This is a friendly heads up for the container liner growers. It is a national problem. Nursery producers at all levels are learning something every day. This is a super large dose to swallow at one time, but I’m just letting you know what is coming; so you can make adjustments and be proactive to the issue, rather than just having to react.
I do not have all the answers. A lot of discussion is occurring in the urban forestry industry based on what is dying and what they are digging up. They may have been the first to recognize some of the problems. They are being vocal about it in several arenas. It does not appear they are wrong.
Fault will likely be shared by the propagator, the producer and the landscaper; as contributing to one or more of the following: root bound container liners, roots planted too deep in containers, plants planted too deep in the field, cultivation or erosion adding additional soil, too few roots dug B&B, being planted too deep in the landscape, sinking into loose backfill, mulched too deep, etc.
We also realize that plants die for many reasons besides being planted too deep or by girdling roots. I believe these problems can be managed when everyone involved tries. Have a Great Day!