New Packaging Promotes Optimum Plant Root Growth

A new range of packaging, specifically developed by Hamilton’s Convex Plastics to promote optimum plant root growth, has been shown to significantly improve root density in seedlings.

Impregnated on the inside with a proprietary additive that promotes dense root growth, the new Rootrol planter bags have been successfully trialled on avocado and native tree seedlings, and are expected to provide similar results on other plant varieties as well.

Past Chairman of the New Zealand Avocado Nursery Association, Ken Oemcke, trialled the Rootrol bags over a three-year period at his Tauranga nursery on Avocado seedlings until 28 weeks of maturity. Ken, who retired recently after running his own nursery for 30 years, was impressed with the Rootrol packaging and is keen to encourage its use.

Ken says, “It’s definitely advantageous and I would certainly recommend it to other growers. The trials clearly showed that using Rootrol produces a superior rooting system. It bulks the root system and provides a better density of root, which I believe will result in a superior tree.”

The trials showed that seedlings planted in Rootrol bags produced a denser lateral root system than the standard control seedlings, which had an overall sparser root structure.

Convex Plastics Technical Manager, Andrew Sheerin says, “Although we haven’t yet tested the mortality of mature trees grown from seedlings in Rootrol, it would be reasonable to expect that the resulting denser root system would improve their stability in environments prone to flooding, high winds and erosion.”

While it’s not unusual for seedling growers to use special compounds to promote optimum root growth in seedlings, these are normally manually applied to the inside of the planter bags, which can be extremely labour intensive and messy.

Andrew says, “Rootrol offers growers the convenience of being able to buy ready made bags with a growth enhancing additive already impregnated on the inside. All the growers need to do is plant their seedlings as normal, with no additional labour investment needed to turn the bags inside out and paint them with compounds such as copper.”

Convex Plastics is offering seedlings growers the opportunity to evaluate the benefits of Rootrol for themselves by conducting free trials on a portion of their crop. Andrew says this will enable growers to compare the root systems of the seedlings grown in the Rootrol with the their normal seedlings in a fairly low-risk way, and will enable them to make an informed decision about its potential value to their business.

Seedlings growers wanting to carry out a free trial of Rootrol packaging should contact: