A mixed bouquet of advice for tending to your garden in late summer, adding native plants

The last part of August is time to clean up raspberry canes if you have not yet pruned back the branches of canes that bore fruit this summer.

Traditional raspberry plants have canes that turn brown and dry up after producing fruit in July. Cutting these old canes right to the ground makes way for the new growth that can then be tied to supports for a great harvest next year.

An exception to the August cutback are the ever-bearing or fall-bearing raspberry varieties. These can be left to grow as long as they continue bearing fruit.

Q. I am considering adding more native plants to my landscape. What natives do you recommend and is it true native plants can survive on rainfall alone? — J., Email

A. First, the bad news. How much water a native plant needs depends on the soil, sun exposure and wind exposure. The good news is that once established, the plants native to Western Washington can thrive on rainfall alone.

Consider adding Oregon Grape or Mahonia, huckleberry, salal, sword fern and vine maples. Many local nurseries now stock native plants like these in containers for easy planting.

A visit to the Rhododendron Species Garden in Federal Way is another way to learn about which native plants do well, and this nonprofit also has a nursery. Visit Rhodygarden.org for details.

One more addition to your native landscape could be large rocks and boulders. You can’t kill a good rock.

Oregon grape (Mahonia) grows in tall clumps.
Oregon grape (Mahonia) grows in tall clumps.

Q. When can I prune my floppy hydrangea? — D.H., Bonney Lake

A. You can prune any irritating plant whenever the pruners are sharp. This means when a plant blocks a pathway or when flowers droop onto the ground, if you don’t like the look, get snippy with it. I suggest you follow each branch in towards the center of the shrub and clip about two thirds of the way back or even remove the lowest branches by cutting right to the base of the shrub.

When you harvest hydrangea flowers in summer, it gives the plant time to make new growth before fall so you will still get blooms.

The best time to prune hydrangeas to shape or renew the shrub depends on the variety. The Pee Gee or paniculata hydrangeas with pointed blooms can be cut back by one third in February or March.

The old-fashioned big leaf hydrangeas with round blooms do best when never pruned, or when the oldest branches are removed to make way for fresh new growth.

But prune anything dead, diseased or damaged any time of the year. In summer, if your hydrangeas suffered from sunburn or drought, cut them back. Life is too short to put up with brown flowers and floppy branches.

Crocosmia ‘Lucifer’ is a favorite non-invasive cultivar.
Crocosmia ‘Lucifer’ is a favorite non-invasive cultivar.

Q. I planted a summer bulb with bright orange flowers called crocosmia. The blooms were great and the hummingbirds loved the flowers. Now, however, the flowers are gone and what is left are seeds forming at the end of the stems. Do I cut these off? I want the flowers to return next year. — W.T., Enumclaw

A. Yes, you can remove the seed pods from your crocosmia plants now or you can ignore them and cut the plants to the ground in the spring. Crocosmia are so enthusiastic that they will spread and bloom again no matter what you do.

In small gardens, it may be best to plant this summer bulb in containers that you can move out of sight once the blooming show is over.

Marianne Binetti has a degree in horticulture from Washington State University and is the author of several books. Reach her at binettigarden.com.