Master Gardener: Be on the lookout for invasive jumping worms

Preventing the introduction and spread of jumping worms are the only proven forms of management.

IMG_8361 jumping worms by Beth Solie.jpg
Photo of jumping worms taken by Beth Solie. Photo courtesy Minnesota DNR

Dear Master Gardener: I noticed a jumping worm this week. I started digging around my mulched beds and my whole yard is infested -- front, side, and back! I must have picked out 100 today, but there have to be thousands. They are really making a dent in the soil already! Any ideas on what to do? It has to be from the commercial mulch I bought this year. That is the only thing I can think of that got in all my different beds throughout the yard.

Answer: I am so sorry to hear you have jumping worms! Please report your jumping worms to at the Minnesota Department of Natural Resources or call her at 651-259-5090. In your report include close-up photos of individual worms with a clear view of the location of the clitellum (collar-like ring around the body). You can also include photos of the soil if it has a “coffee-grounds” look.

Related story: Ask the Master Gardener: Keeping a garden colorful through autumn There are a number of plants that bloom in the fall.
It is very frustrating for gardeners who are experiencing jumping worms because unfortunately there are no management recommendations. There are no pesticides labeled for worms, including jumping worms, in the United States. No products can legally be used in Minnesota as pesticides if they are not labeled and regulated by the EPA and the Minnesota Department of Agriculture. Prevention is the only known management for worms. Since you have jumping worms, please consider participating in a citizen science project to help the University of Minnesota better understand possible jumping worm management options. If you are willing to help, please go to the following website and fill out the Google form. Angie Gupta at the U of M Extension will follow up with a Google document specifically for you and your project. Here is the website: .

This reader lives in the Twin Cities area. All gardeners in Minnesota should be on the lookout for jumping worms in soil, potted landscape plants, mulch or compost. Preventing the introduction and spread of jumping worms are the only proven forms of management. If you suspect you have jumping worms, please report it to the Minnesota DNR.


Dear Master Gardener: My late blooming panicle hydrangea has very few blossoms. What could be wrong?

Answer: There could be several reasons why your hydrangea paniculata isn’t blooming well. Panicle hydrangeas need at least four hours of bright sunlight per day -- six is even better -- to get the most flowers. Could you have over-fertilized your hydrangea? Less is better when it comes to fertilizing hydrangeas -- they often bloom better if a little starved. Too much nitrogen will promote lush foliage at the expense of blooms. If there was a late frost in April or May it could have damaged the buds. Pruning at the wrong time could also be a cause of few blooms. Hydrangea paniculata should be pruned in late fall, winter, or very early spring.

Related story: Ask the Master Gardener: How to take the creep out of creeping Charlie As shade increases, it becomes more difficult to sustain a lawn and more favorable for weeds like creeping Charlie.
Dear Master Gardener: Help! I’ve never raked and swept up so many acorns in my life! What is going on this year?

Answer: Everyone seems to be talking about this year’s bumper crop of acorns. Oaks make up about 9% of Minnesota’s forests and they are a common tree found in many homeowners’ yards. With so many oak trees around it isn’t surprising that many homeowners have noticed the enormous crop of acorns produced this year. According to “My Minnesota Woods,” “a single mature oak tree can drop up to 10,000 acorns in a single year. Generally, large acorn crops for oaks occur every two to five years.” It looks like this is one of those years!

Dear Master Gardener: I bought some bargain raspberry plants that had no labels -- hence the bargain. The nursery knows they are University of Minnesota recommended varieties. What do I need to know about planting and caring for them?

Answer: Raspberries can successfully be grown in most parts of Minnesota. They have perennial roots and crowns, but their canes live for only two summers. Most raspberries are summer-bearing varieties. During the first year, the new green cane (primocane) grows leaves then develops a brown bark and is dormant in winter. In the second growing season the cane is called a floricane; it produces fruit and then dies. New primocanes are produced each year, so fruit production continues year after year. Raspberry plants need full sun to produce the most fruit and will start producing fruit the year after they are planted. Grow raspberries where they will have good air circulation to reduce disease problems, and avoid windy spots because they dry out easily. Plant them in well-drained soil making sure to keep the crown of the plant one to two inches above the ground. When you place the plant, loosen and spread out the roots, and try not to wrap the roots around in the hole. If there are any long or unruly roots, they can be trimmed off. Rabbits are your enemy -- they love to eat the canes in winter. A chicken wire fence will help prevent rabbit damage. And then the Spotted Wing Drosophila will break your heart when the berries are ripe!

You may get your garden questions answered by calling the new Master Gardener Help Line at 218-824-1068 and leaving a message. A Master Gardener will return your call. Or, emailing me at and I will answer you in the column if space allows.
University of Minnesota Extension Master Gardeners are trained and certified volunteers for the University of Minnesota Extension. Information given in this column is based on university research.
What To Read Next
Get Local