Extending the season in zone 7b

Pot in pot gardening is a method that’s typically used for propagating slow growing plants or tall plants (trees) that could fall over in the wind. Instead of planting directly into soil, a hole is dug, an empty plastic pot is placed into the soil, and a potted plant of the same pot size is placed into the pot into the ground. Pot-in-pot!

I really struggled last spring with just how slow it was to for the green stuff – anything green – to start to take over the landscape, and one of the tests I ran was to try pot-in-pot gardening.

My plan was to pre dig holes so that I’d be able to buy greenhouse plants and pop them in the ready holes as soon as they’d be safe from frost death. In the meantime, I’d place a pot-in-pot in the holes to test whether this would be a winter plant survival strategy.

So, what to put in the holes over the winter? I had this oversized plantain lily Hosta. I didn’t really like it. It needed to be divided. And it was growing in an area that I want to convert to lawn. Perfect specimen!

I can’t actually remember what I used for soil, but my go to is coconut coir, compost, and leca. My local stores don’t carry vermiculite or perlite, so I use leca balls or shards to increase airflow.

I chose an area of our raised border that was overfull of plants. I’m also not in love with these, plants so death was an acceptable outcome here too. I dug five holes and stuck the plantain lily pot-in-pots in. I chose to remove the bottom pot over the winter, and replaced it with just the plantain lily pot.

I’ll call this a success!

All five pots are showing signs of growth! 0% winter deaths is an outstanding result.

I’ve moved them to a warmer and sunnier area to speed up their growth. In the meantime, I could choose to buy five new plants to put in these holes while the hostas grow in.

For future iterations, I’m considering insulating the pot in the ground with shredded tree fiber insulation (this stuff is readily available in Norway). I think I’ll get some extra growth from that. And if the pots with the plants are a little higher over the garden bed, frost might flow around them, and then cold air can drain away and off the raised bed. I’m hoping for a little later fall earlier spring greenness from that.