Autumn containers and perennials

I promised on the Steven & Chris show that I would give information about perennials in container on this blog. ?Well here is a condensed version of what I said, what I wrote in the Globe and Mail and the best of all a reader’s suggestion.You have to insulate containers before you use them and here’s what Clarke Kirkland of Toronto says:”What you do is buy a spray can of foam insulation from your local hardware and then spray it on about 1 and a half inches thick all around the inside of the pot. ?I put the pot on its side and then go backk and forth across the side laying down the insultation. ?For round pots I do about one third of the pot at a time and let it dry and then roll the pot and do the next third. ?Repeat until done.?My pots are about 4 years old and the foam still has its integrity and the cedar, tamarack and juniper in them are growing well in my Cabagetown garden.”This is such a good idea I’m going to adapt it to my own containers when I start getting them ready in a few weeks. ?If you want to watch the segment, click here.Here are some of Margaret Serreo’s suggestions

• Don’t use too many elements. Keep it down to a maximum of five including what you’re using for a mulch if it’s stones.
• Make one stunning evergreen the focal point of the container; this will be your upright. Then add contrasting perennials in harmonizing foliage colours, grasses and perhaps one or two small boxwoods which you can shape in almost any way you like.
• Use your own potting soil mix (don’t use the same stuff you use for annuals): half horticultural sand, half topsoil and compost. Add a layer of mulch about 2 inches thick at the top.
• Water deeply until it comes out the bottom. Keep on doing this until it freezes.

I’m getting the autumn e-letter ready, so if you’d like to sign up I’ll add you to the list.??