Ask a master gardener: managing bluebells | BrainerdDispatch.com | Brainerd, Minnesota

Ask a master gardener: managing bluebells

Posted: July 3, 2012 - 3:59pm

Dear Master Gardener:

I have some beautiful bluebells growing at the edge of the woods and we have enjoyed them, but now they are spreading rapidly, even into our lawn. How can I manage them or get rid of them?

I strongly suspect that you have creeping bellflower, Campanula rapunculoides, which, as its common name implies, likes to spread. It is a perennial that is very invasive, especially in moist, shady areas. Its basal leaves are large and heart-shaped, but as the plant grows upward the leaves narrow and a flower stalk 1-2 feet tall emerges.

In bloom the flower stalk produces numerous downward facing, blue-violet, bell-shaped flowers mostly on one side of the flower stalk. They bloom from July-October. Creeping bellflower is very difficult to eradicate, largely because of its deep and complex root system. The main root is a large, fleshy tuber, often 6 inches deep. But there are numerous shallow, fibrous offshoot roots that can extend some distance and break off easily in hand removal. Creeping bellflower is resistant to 2,4-D but responds to glyphosate (Roundup). Because glyphosate kills every plant it touches, it is best applied by pouring some into a small dish, wearing gloves and wiping the bellflower leaves individually with a sponge or cloth soaked in it. Late spring and early fall are the best times to do this. Treatment may need to be repeated for several years.

Dear Master Gardener:

The rabbits have eaten many of my perennials. Are there any plants rabbits won’t eat?

Minnesota gardeners are reporting a high level of rabbit browsing in their gardens this summer. Like deer, rabbits will eat just about anything when they are hungry. You will notice signs of rabbit damage when you see your herbaceous plants, especially young ones that have been nibbled down to the ground. To protect your trees from rabbits, place a cylinder of ¼ inch mesh hardware cloth or plastic tree guards around the trunk. If you have a prized perennial that you don’t want devoured by a rabbit you could put a cylinder of hardware cloth around the plant, but unfortunately it isn’t very attractive.

Repellents may deter them, or at least reduce the damage. Sprinkling dried bloodmeal on the soil around the plants may work, as rabbits do not like the smell of blood. It will have to be reapplied after it rains.

According to several Minnesota sources there do seem to be some plants that rabbits avoid. Following is a list of some “rabbit-resistant” perennials: Ajuga, Allium, Artemesia, Astilbe, Baptisia, Bergenia, Bleeding Heart, Coreopsis, Daffodil, Daylily, Fern, Foxglove, Goat’s Beard, Hardy Chrysanthemum, Hollyhock, Iris, Lady’s Mantle, Lily of the Valley, Peony, Russian Sage, Salvia, Tiarella, Virginia Bluebells and Veronica. Rabbits seem to avoid a few annuals such as wax begonia, marigolds and geraniums.

Dear Master Gardener:

My leaf lettuce is starting to taste somewhat bitter and stalks are shooting up. Should I pull it out?

Lettuce is a cool weather vegetable that grows best at 60-65 ° F. Leaf lettuce grows quickly and is the easiest type of lettuce to grow. During the heat of July leaf lettuce and spinach tend to bolt (go to seed) and taste bitter. When it bolts, pull it out of your garden and replace it with broccoli, cabbage, or cauliflower for a fall harvest.

Dear Master Gardener:

The mosquitoes this year are horrifying! I get eaten alive working in my gardens. Can I spray my whole yard to get rid of them?

With the amount of rain we have received, the numbers of mosquitoes have significantly increased. Spraying your entire garden for mosquitoes is not practical. There are precautions you can take to protect yourself when you go outdoors to garden. Minimize your exposure by avoiding times when mosquitoes are most active, such as dawn and dusk. Mosquitoes are less active in bright sunlight and during windy conditions. Wear light-colored clothing with a long-sleeved shirt and long pants and protect yourself by using an insect repellent containing N, N-diethyl-meta-toluamide, also known as DEET. The clothing and DEET suggestions are also recommended for deterring ticks.