What can I do about grey mould on my strawberries?

Not much. Grey mould (a.k.a. botrytis) affects the flowers, leaves and fruit of a diverse variety of plants, including strawberries, and extended periods of rainy weather greatly increase the chances that it will show up in your garden.

Rarely does botrytis get so bad that it takes out most or all of a crop, and even in years when it is more pronounced than usual, spraying isn’t the recommended way to deal with a problem that will go away on its own as long as the hot, sunny weather we are currently experiencing sticks around.

For now, pick off and dispose of any affected plant parts. Once things finally dry out, keep watering to a minimum so that both the plants and the ground get an opportunity to experience a moisture free period between waterings. That way you don't accidentally replicate the conditions that gave rise to the mould in the first place.

What is the difference between a tree peony and a regular one?

The peonies that are most commonly seen in gardens are herbaceous perennials that die down to the ground each winter and sprout again the following spring. They usually grow to about three feet in height and are one of the longest living and easiest to maintain of all of the herbaceous perennials. It's not uncommon for one plant to live 30 years or more.

Tree peonies, on the other hand, are shrubs (not trees, despite their name) and, on average, grow to about six feet tall. They do not die down to the ground each fall like their herbaceous counterparts, but instead keep their branches from one year to the next. They should be pruned every year like any other shrub to optimize their shape and to remove any diseased or damaged branches.

Herbaceous peonies are readily found in garden centres in a variety of colours and flower classifications and tend to be reasonably priced considering what you’re getting for the money.

Tree peonies can be a bit harder to find and often carry hefty price tags, so they’re not the sort of thing gardeners tend to impulse buy. Still, this is one plant that it’s worth paying the big money for and if you invest the time to figure out which variety would work best in your garden and then shop around to find it, you will likely be pleased with your purchase.

To submit a question to Riverview master gardener Vanessa Farnsworth, please send her an e-mail at vanessa@gardenmuse.ca or visit her website at www.gardenmuse.ca.