I was so inspired by the air-pruning video I shared with you a few days ago that I immediately decided to try out this seemingly magic method of improving plant growth. I already had imminent plans for sowing some Sweet Pea seeds as I am planning on training several Sweet Pea plants to grow up and through the crochet jute and willow garden screen that I have also been working on recently. The willow garden screen project is my experimental version of location-specific vertical gardening.

As my back yard is only very small I needed to develop some air-pruning pots that would be more size-appropriate than the 5 gallon buckets they used in the video. But I also wanted some containers that would reasonably accommodate the Sweet Pea plants. I have grown Sweet Peas in my yard in the past using moderately-sized containers and with a bit of care they successfully reached their full six-foot height.
A further consideration was that I need to be able to attach some of the plant pots to the back of my yard gate, so lightweight containers with ‘attach-ability’ were additional factors to bear in mind. And, as I frequently do, my preference was to use upcycled materials for this project too.
The solution to my air-pruning plant container conundrum is … four-pint milk cartons! These milk cartons satisfy all of my requirements – lightweight, with built-in handles for ‘attach-ability’, moderately-sized and easily re-designed for their new purpose … and upcycled.
Fortunately, I had a number of these milk cartons readily available as I had saved them ‘just-in-case-I-need-some’ – I’ve made milk cartons into standard-type plant pots on previous occasions. But this time my design plan was rather different.

I began by making a large planting hole at the top of each carton by cutting around the original milk carton’s opening. You can see I have cut high above the carton handle to leave the whole handle intact. Around the sides and front of the carton I dipped down a little lower with the scissors to make a reasonably-sized opening to give accessibility.
Next I pondered on the best way to ventilate the sides of the cartons to provide the air-pruning effect. The air-pruning video showed circles cut out of the sides of the 5 gallon drums. I emulated this on the first carton, cutting out relatively large holes all around it.

However, I then wondered if different shaped holes would be more or less effective at air-pruning. To test out my curiosity, I have decided to make different shaped holes in some of the cartons. Two cartons have circles, two have wide vertically-oriented ovals and the remaining two have a series of narrower vertical vents. It will be interesting to see if the different-shaped vents in the containers make any difference to the plant growth.
Watch out soon for Part 2 of my upcycled air-pruning plant pots project in which I will show you how I made the fabric grow-bags to fit inside the pots.
J Peggy Taylor