Your ability to re-use the plastic insert depends on 1) how long you let the plant grow, and 2) the type of plant. The determining factor is the size of the root mass the plant develops. Smaller root structure = better chance of re-use.
Although it's possible that you will be able to re-use the plastic insert, and we plan to offer refills in the future to cater for this, our advice is that you shouldn't count on being able to do so. For this reason, we use a biodegradable plastic. We want to avoid landfill even more than you do. It costs us a bit more to do this, but we feel it's money well spent.
A few of you have suggested that throwing away the plastic at the end is wasteful. Like we said, we want to avoid landfill more than you do. The main reason we started this business was because of our belief in sustainability. Although throwing away waste items is never ideal, we encourage you to think about our product in the context of your available alternatives.
- The average American meal travels over 1,500 miles from farm to table. We're aiming for 15 feet. We're saving food-miles.
- The average American produces over 1,500 lb a year in waste, much of which is packaging. We're aiming for zero food-packaging.
- Our food system in the US throws away around 40% of what we produce. This food waste is worth around US$121 bn pa. Producing this food that gets thrown away wastes water, resources, land, labor and energy. By growing food at home we aim to get food waste down to 0%.
So yes, it is a bummer if you don't end up being able to re-use our little piece of (biodegradable) plastic, but relative to your alternative we're still WAY ahead.