I got to thinking that I might try PVC for starter pods. My reasoning is that there are so many sizes and I can cut whatever length of pipe I want. Not to mention forever reusable and so easy to move up a size to transplant toms and peppers. Place smaller one inside, bury the smaller pipe and lift, instant transplant, just tamp and add water. Is this a reasonable idea or are there flaws that anyone can think of that will make it not work? Except for no bottom but I have that figured out, I think, if I can the right size caps for the sizes of pipe I would use. Aeration would be really easy if you drilled holes along the pipes to help prevent damping off and getting too wet. Only drawback there is roots trying to grow through the holes. I figure start with 1 inch, then 2 inch, then 3 and then 4 inch or even bigger for the final size before moving outdoors.
It's an extremely clever idea and I hate to put a dampner on such creativity. PVC, however, is made from toxic chemicals and additives that can "migrate' out of the plastic. In other words, they are not 'bound' to the plastic and can leach into your soil, food, etc.
I have seen people using pipes to blanch celery and leeks, but not really for seeds. I have so many regular plant pots that I really don't need anymore, but I know lots of people that make their own out of paper, loo roll inners and yoghurt pots. I would be concerned about the chemicals that ecogirl mentioned. We have a similar problem here when people started using old railway sleepers to create raised beds. The tar and preservatives leeched into the surrounding soil, similar thing with old tyres used for spuds. A great idea, but I would do plenty of research before committing.
I will have to find the data again on PVC to see when it starts to break down, I thought it was like 150 years or more but don't remember. I know there is a ton of white PVC in the cities water lines that we drink out of so it can't be too bad for you. As for tires, I would be much more concered about the toxic crud that has stuck to it while being driven on than it breaking down using it for planters. If I find the EPA's breakdown sheets I will post it.
It is a great idea and you can find the caps in the same sizes as the pipe but they are much more expensive. As for leaching out any toxins i do not think so since it is also used for potable waterpipe. My hubby also built some rabbit fences around our raised veggie and flower beds out of PVC and plastic fencing, see pictures. They are very light and easy to store and move. This picture is not so good will do a better one tomorrow. raised beds ( photo / image / picture from happyzinnia's Garden )
Well I have found a lot of stuff on the leeching of chemicals and it is confusing as h***. Black PVC is not food grade nor should it be used for food appplications, ever. White standard PVC when exposed to highly basic or acidic compond for extended periods starts to break down and release some chemicals that can be harmful. Under normal use, the best information I cold gather was it takes between 2 and 250 years for it to start breaking down and release harmful chemicals. Oh well, was a thought, maybe I can find something else that has the sizes that I was thinking to make growing and trasnplanting easier for toms, peppers and such. Until then I guess it is coconut coir and peat moss pots. It would actually be nice to find solid pots the exact same size as the peat/coir pots to make it easier to transplant and not disturb the roots of most plants. Having a coir/peat pot that is a straight up and down cylinder would be nice too for both transplant purposes and space, even better, square/cubical ones.
