Aside from spring and fall clean-up, I find June is the next busiest maintenance time in my perennial gardens.
Today, I would like to share some tips for keeping your perennials looking their best.
Most spring bulb foliage has died back and can be removed unless it is hidden under other plants, in which case it can be left to decay out of sight.
The early-blooming, evergreen perennials such as Arabis, Aubretia, creeping phlox, and perennial alyssum, need to be trimmed back and tidied up now.
If you wait until fall or next spring, you will be cutting off next year’s flowers.
Cut off iris and peony flower stems when blooms are finished. Be sure to cut them well below the foliage to avoid leaving ugly, poking stems.
Oriental poppies tend to die back after blooming. Their foliage can be cut right back and will re-grow somewhat.
These plants are best planted behind some later-blooming, large plant to hide them and the empty space they leave after their three week, spectacular show.
Any plant that self-seeds should be dead-headed before the seed heads mature unless you want many babies.
Blue fescue grass is blooming now. Unless you want it to create a meadow, it’s wise to cut off the flower heads.
The grass is mainly grown for its blue foliage so the flowers are not of great significance.
Another plant that must be cut back before it seeds is the silver-leaved snow in summer.
It will seed vigorously amongst other plants as well as rapidly spreading by roots and can be a real menace, invading other plants.
As soon as it has bloomed it’s a good idea to reduce the diameter of the plant by one half to keep it under control.
It is best used as a ground cover in an unirrigated place where it won’t cause problems.
I often have many culinary thyme babies. These have proven very useful to fill in a slope where I don’t water. They are free and can be replaced easily if I find other plants for those spaces.
Shearing an inch off silver mound artemesia now will prevent the plant from splaying open, as it does when the insignificant flowers open.
As you work through the garden, be sure to watch for weeds in your plants. It is amazing how well they hide. The sooner you get them out the better as some form substantial roots.
I have two favourite tools for perennial deadheading. When the whole plant is being dead-headed at once, such as creeping phlox, I use long-bladed shears.
For cutting individual stems, I use grape pruners. They have scissor-like blades with pruner spring handles, making them much easier on my hands than using scissors.
