To prune or not to prune perennials in the fall?
That’s a question that comes up often.
In fact, in the great majority of cases, it’s not necessary or even desirable to remove the foliage and floral stems on perennials when autumn comes. Leaving everything in place promotes snow-cover trapping, the best insulator there is, thereby offering your plants better protection against severe winter conditions.
The dried stems and dead leaves also serve as winter shelter for numerous organisms that are useful to the garden, such as native ladybugs. Plus, the fruit and seeds that survive at the end of the season are a treat for certain birds.
On top of all that, the leaves and stems of perennials nourish the soil as they decompose. And no need to worry, there won’t be a big cleanup to do in the spring: plant residues will quickly be hidden by the new foliage, and will carry on decomposing over the summer, safely out of sight.
Finally, the dried inflorescences and the foliage of some perennials, especially grasses, offer a wonderful spectacle in the fall, and even in winter. By leaving them as they are, you benefit from their beauty while saving on time and effort.
When spring comes, if the sight of browned floral stems bothers you, you can cut them into small pieces and deposit them at the base of the plants. In addition, if you find that the yellowed foliage of certain grasses takes too long decomposing, you can prune it early in the spring and use it as carbon-rich material for your compost.
Did you know that by allowing the organic matter produced by plants to decompose where it lies you have less need to apply compost or fertilizer to your flowerbeds? Mother Nature does the work for you, and the soil gets richer 100 percent naturally.
A few exceptions
Perennials frequently affected by fungal disease and pests should be pruned. Never compost infected or parasitized residues, as these can become a major source of contamination.