Ask the Expert

Should I mow my pollinator garden?

Question: I’ve planted flowers and left my yard unmown for several years for a pollinator garden. Some of my neighbors think I should mow it this year. Should I? If yes, how short? Answer: Jonathan Foster, Home Horticulture Outreach Professional I’m assuming the issue is whether mowing is beneficial to the pollinator garden, and not […]

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Can you give me recommendations on how to control purple loosestrife?

Question: Can you give me recommendations on how to control purple loosestrife? Answer: Jonathan Foster, Home Horticulture Outreach Professional This is purple loosestrife (Lythrum salicaria), the pretty, but wildly aggressive colonizer of fields, wetlands and roadsides all across Maine. The bad news is that it’s extremely difficult to control–it seeds prolifically, forms dense and resilient […]

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What is the grayish white growth on my lilac trees?

Question: I have two 20-year-old lilac trees that have a gray-white fungus all over it’s bark, both old and new growth. It is silky to touch. I have taken out some dead branches and it seems as though some of the foliage is dying in places. Is this something I should be concerned about? Is […]

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What is a good method for getting rid of Canada thistle?

Question: I have wildflower gardens that wraps around my house. In one section, I am battling what I believe to be Canada thistle. Initially, I was cutting off the stems at the base and spraying the remains with 30% vinegar. However, because I have such a large patch of it I found that to be […]

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Why are the leaves turning brown on my Sunburst Locust tree?

Question: Some branches of leaves are turning brown on my Sunburst Locust tree. There are no webs so I’ve kind of ruled out the webworm. What could be causing the problem?  Answer: Jonathan Foster, Home Horticulture Outreach Professional There are a number of reasons why tree leaves can brown, both biotic (e.g., pests and pathogens) […]

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How should I proceed with the asparagus that I planted?

Question: I planted asparagus about six weeks ago, in trenches 8-10″ deep, following directions. The directions also said to cover up new growth when it came, but it came almost overnight, with stalks several inches high, which seemed uncoverable. I haven’t done anything, and now they are feathery and plentiful…should I cut them off and […]

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When should I prune new grape plants?

Question: I have a grape pruning question. I planted three new grape plants in late May. I have since learned that I should have pruned them down to 1-2 primary stalks after planting, but I didn’t do that. I am wondering if I should do this now or wait until their dormant period, Jan-Mar next […]

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