Greebouse and Nursery - Alternatives for Plastic Pots 4

There are many alternatives to plastic pots being offered for the greenhouse and nursery trade. The following is the fourth in a series of posts on this subject (information from the University of Maryland).

Plastic pots benefited the horticulture business for many years, enabling growers to sell product at just about anytime of the year in an attractive and inexpensive package. Plastic pots are not gone just yet but consumers are interested in products that are environmentally friendly. Plastic is not conceived as environmentally friendly or sustainable material. Limited oil reserves and concern about using anything that is not renewable has changed many of our notions about plastic pots and trays.

This is an important enough topic that we decided to have it as subject matter and discussion point at the 2009 Chesapeake Green Conference in February. Greg Trabka of Ball Horticulture Company laid out several interesting alternatives to plastic pots at the Chesapeake Green Conference. The alternatives vary from pots made from Coir (coconut fiber) and peat moss, wheat based compostable pots, potato flour pots that are biodegradable, and rice hull pots that are biodegradable.

One thing to keep in mind is that the largest pot that can be made so far that has the stiffness or integrity to stand up is a 1 gallon container. None of the alternative pots presently on the market hold up well when growing crops outdoors for several moths or longer. It would be great to have mum pots that held up outdoors and pots that perennial growers could use in their multi-month production of plants in outdoor growing conditions. Alternative pots are still evolving and there are some problems to work out before growers adopt them widely for use in greenhouse floriculture.

Grower concerns include how to make these alternative pots last through the production stage and still be an attractive package for the consumer. Another thing to consider is how well the pots will hold up at the garden centers and how the consumer will get the plants home without making a mess. How to keep the rootballs from imploding before making it to the planting site is the main concern.

Several growers pointed out that many consumers take plants home and let them sit around for a couple of days before they are planted. They are concerned that customers will let roots growing through pots dry out before getting them into the ground. This last problem can be solved with educational literature to let customers know to get plants into the ground quickly.

What is a little confusing for the public is that there are home compostable pots and industrial compostable pots. Home compostable pots can be thrown on the home compost pile and will bread down with little effort. Industrial compostable pots have to be placed in windrow compost piles and turned regularly to get them to break down. The compostable pots appear to be better suited to mechanical planting systems and can be handled in a lot of ways like the familiar plastic pot. Bio-degradable pots break down when planted in the landscape or garden. These biodegradable pots are probably the best system but the trick is have the pots hold up in the production greenhouses with varying length of growing times and growing conditions.

Information from the February 20, 2009 edition of the Greenhouse TPM/IPM Bi-Weekly Report from the University of Maryland Cooperative Extension Central Maryland Research and Education Center http://www.ipmnet.umd.edu/09Feb20G.pdf.