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Showing posts from 2018

Help fight new invasive insect in Minnesota

The Minnesota Department of Agriculture (MDA) issued a news release today to warn about a new invasive insect pest that has been found in Minnesota, the elongate hemlock scale (EHS), Fiorinia externa. It was detected on wreathes and other evergreen decorative items from Home Depot and Menards.

MDA is asking residents that bought evergreen decorations at any retail chain stores to “burn the
items, or bag them and dispose of them in the trash once the items are no longer useful for decoration. The evergreen items should not be composted.” While EHS has only been found in Home Depot and Menards, it is possible that it may be present at other retail chains.

The Wisconsin Department of Agriculture, Trade, and Consumer Protection issued a similar warning earlier this week after finding EHS in several retail chain stores.

This is the first time that this invasive insect pest has been found in Minnesota. While EHS prefers hemlock, it will feed on a variety of evergreens, including spru…

How to make your Christmas Tree last through the holidays & More fun facts!

There it is...your Christmas tree in the living room (hopefully not dropping needles) standing ready and waiting to help your family celebrate the holidays!  But did you know exactly what you were buying? Which trees are native? What tree will retain its needles better? What's the best the way to keep my tree fresh throughout the holidays? Here are some facts about that all important purchase for your family.
What's the most popular tree in MN?  There's not great data to share here. But the University of Minnesota Forestry Club has tracked their sales and they say there are two front runners--Fraser firs and balsam firs, but pines don't make the cut. Fraser firs make up almost half of those trees sold by the club. This tree originally came from the southern Appalachian region of Virginia and North Carolina, but it's also grown in Minnesota in certain situations. Some refer to it as the “southern balsam fir."  It has a bigger trunk and larger branches compared…

Landscape Design Basics Workshop: A great holiday gift!

Class information /registration: Landscape Design Basics

Do you have that really tough gardener to buy for? Someone who seems to have everything, and is

always branching out into new gardening? Do you have a friend or family member who just bought a new house and wants to get their hands dirty this spring by re-doing the landscaping? Or are you that someone and need to drop a few hints that a landscape design workshop would wrap up nicely as a holiday gift?

Landscape Design Basics Workshop is just the ticket to getting started on that new yard and garden project in 2019. Throughout the five classes, students work on their own  entry garden and / or patio or deck garden. Class exercises and lectures revolve around the process of sustainable design, considerations and principles, plant selection, concept plans and concept lines, landscape spaces, implementation, etc. Weekly class critiques provide valuable feedback from instructors and their peers. Exercises help students to practice t…

Houseplant Patrol: A new webpage for managing indoor pests

In these cold wintry days, we turn to tending our indoor gardens. Houseplants are really fun - tropical, usually lush, and their blooms can brighten any home. But there are also pests sometimes lurking in our plants. Because we are growing these plants in unnatural conditions (indoors), there are no natural predators managing pests numbers. That responsibility falls on us as plant owners.

Our new webpage Managing insect pests on indoor plants will provide help to those dealing with houseplant pests. Prevention, detection and options for managing these pesky critters are included. Gift tip: If you are giving a houseplant to someone, print out a copy to include. We hope you find it interesting and helpful.

You can also get answers from Extension to your gardening questions - indoors and out - every Saturday on Smart Garden, 8-9am, on WCCO radio AM 830.

- Julie Weisenhorn, Extension educator

The Challenges of Overwintering Rosemary

Rosemary is one of my favorite herbs and I have tried growing it indoors for several years, most years I have ended up with a dead plant. For a plant that is so easy to grow outdoors, I am still trying to figure out how to successfully overwinter rosemary.

Sunny good light is a given, a must for maintaining herbs indoors through a Minnesota winter. I think the watering is the tough part…..I think rosemary does not like to dry out indoors. And like most herbs, if thrives on well drained soil.

And then there is the mildew issue….so easy to get mildew in the winter indoors.   If all else fails, there are our wonderful garden centers…where healthy rosemary is waiting for us, especially colorful and lovely for Christmas gifts.
The Rosemary Challenge Theresa Mieseler, local herb guru and owner of Shady Acres Herb Farm (, Chaska, MN has this to say about growing rosemary indoors:

Rosemary can be somewhat of a challenge to grow indoors.
1.Most important is that it was grown in…

Just in time for the holidays: Poinsettias webpage

If you have a new poinsettia this holiday season, or still have one from last year, you'll want to check our the new Extension webpage on Poinsettias and how to help them re-bloom, and even thrive all year long!

I was never a fan of poinsettias. They were too holiday-specific for me. In the past, I thought having a poinsettia after Christmas was like never taking down the wreath on your door. I always  thought poinsettias looked pretty dull and color-less after the bracts dropped (the bracts form the  "petals" on the plant, but actually modified leaves).

However, researching and writing this new webpage has renewed my interest in poinsettias and I am looking forward to bringing one (or maybe more) home with me this weekend.

Take a look at the new webpage. I hope it brings
you tidings of great joy - and a healthy poinsettia.

Author: Julie Weisenhorn, Extension Educator - Horticulture

Meet a new invasive tick: the Asian longhorned tick

An advantage of winter and its cold weather is there are certain pests for which we do not have to worry about until spring. At the top of this list is ticks. However, to remind us that trouble is never far off, the Centers for Disease Control and Prevention (CDC) recently issued a news release, to warn of a rapidly increasing threat from a new invasive tick, the Asian longhorned tick, Haemaphysalis longicornis.
A serious pest Originally from China, Korea, Japan, and other areas of east Asia, the Asian longhorned tick is a serious pest because it can vector many different diseases to not only people but also to pets, livestock, and wild animals.

Asian longhorned ticks can also reproduce without mating, a real time saver, allowing them to produce particularly large numbers of offspring, up to 2,000 eggs at a time.

This invasive tick has since spread to New Zealand and Australia where it is a significant pest on cattle. There are times when Asian longhorned ticks have become so a…

Gift Idea: Good Books for Minnesota Gardeners

Nothing like a cold day in January in Minnesota when you don't have to go anywhere, so you can sit by the fire with a good book! Give your favorite gardener this pleasure this holiday season with one of our Extension Educators' favorite books!

You'll find books by local authors and information about peonies, orchids, native plants and more like zero-waste gardening. Many of these topics are written specifically written for the Minnesota gardener.

Please note, the links are to the publishers' sites but you can find these book at many sources online.

Happy giving and happy reading!

Peonies The Best Varieties for Your Garden by David Michener and Carol Adelman, Timber Press 2017 Do you love to grow peonies or know someone who does? David Michener is the University Services Curation and Manager at Matthaei Botanical Gardens at the University of Michigan, where he manages an award-winning Peony Collection.  Carol Adelman owns a peony farm in Oregon....trusted information fr…

Amaryllis provide a dramatic show (and fun to grow!)

Ah. Amaryllis - a favorite plant to give, get and grow around the holiday season! A member of the Lily family, its enormous colorful flowers give us a sense of the tropics during these cold winter days. Amaryllis are fun for anyone to grow - I've given them to everyone from 4 to 90 year-olds, bosses and colleagues, family and neighbors. They are inexpensive, beautiful and dramatic additions to any home.

But how do you take care of them after they bloom? And why can it be hard to get them to bloom again? Every year people ask us these questions, and while we can't ask the plants, we do have an excellent webpage for all the amaryllis owners out there:  Growing and caring for amaryllis.

If you are giving amaryllis this year, I suggest printing a copy to present along with the plant or emailing them the link to the recipient for future reference. They'll have everything they need to keep their amaryllis healthy from year to year.

Enjoy the holiday season - it's a great ti…

Podcast: Busting Horticultural Myths with Linda Chalker-Scott

As gardeners, we always want to find effective, sustainable solutions to our plant problems. Browsing the internet, gardeners will find many claims about the benefits of numerous plant health remedies. Sometimes, these methods are accompanied by words such as "alternative" and "natural." But how do we know which methods are backed up by science, and which are not?

A new episode of the UMN Extension horticulture podcast "What's Killing My Kale?" approaches this topic, using epsom salts and compost tea as examples. Extension Educators Annie Klodd and Natalie Hoidal interviewed Linda Chalker-Scott, host of the Informed Gardener podcast and Horticultural Myths blog.

In the interview, Chalker-Scott lays out ways that gardeners can determine whether online claims about natural products are accurate, effective, and appropriate for their gardens.

Linda Chalker-Scott is an Extension Educator at Washington State University and manages the Horticultural Myths b…

Making a Holiday Wreath? Avoid the 'killer vine' Oriental Bittersweet

It's the time of year when crafty folks are using greenery and plants from their own yard to make their own holiday wreaths. But here's an attractive plant you'll not only want to avoid, but make quick work to get rid of ASAP--called the "killer vine," the "Boa constrictor" of Minnesota plants, it's Oriental bittersweet (Celatrus orbiculatus).

Once again, the Minnesota Department of Agriculture has pronounced Oriental bittersweet its November "Weed of the Month," and for good reason.  This invasive plant has caused property damage and altered ecosystems with its prolific seed production and aggressive growth.
Is this killer vine in my backyard? The Minnesota Department of Agriculture reports it was confirmed in the Twin Cities metropolitan area in 2010, and since then has been found in multiple counties.

A particularly severe  infestation was discovered in Red Wing and Winona in Southeastern Minnesota.  UMN Extension and Conservation Corp…

Biggest Black Willow in America lives in Minnesota!

Just try to get your head and arms around this story! In early September, a black willow (Salix nigra) tree in Minnesota was named a National Champion by the National Forests organization in Washington, DC. The tree on private property in Marine on St. Croix knocked off the podium a New Hampshire champ. It means its bigger than any other known tree of this species in the United States and is now included in the Champion Tree National Register.

According to the National Forests website, the conservation organization recognizes trees because  "we recognize the beauty and critical ecosystem services provided by our biggest and oldest trees."
What makes a tree a champion? The tree was also named a "State Champion" last year by the Mn Department of Natural Resources. Trees are nominated on a state and national level based on three measurements:
Circumference in inches of the trunk measured 4-1/2 feet from the groundHeight in feetOne quarter of its crown spread in feet T…

VIDEO: Make your garden 'pollinator friendly' for the winter ahead

You’ve planted pollinator-friendly plants in your yard like coneflowers, milkweed, bee balm and more. Now take the next step this fall and create a habitat for Minnesota's native bees that will make your yard pollinator friendly all year long!
As you're cleaning up your fall landscapes this year, think about our pollinators and what you can do now to help them through the winter and in the spring. 
Watch our new video: 'Fall Cleanup for Pollinators' Extension Educator Julie Weisenhorn shows you how to do this in a few simple steps.
FAQ's about 'bee hotels' One of  tips Julie suggests is creating a bee "hotel" for native bees.  Roughly 60-70 percent of bees nest in the ground. The other 30 percent are cavity-nesting, using hollow plant stems or holes in wood.
Here are some common questions about houses for wild bees with answers from UMN Extension Bee Researcher Elaine Evans: 
Q:Is fall the right time to buy or build and install a bee house?
A: Any…

VIDEO: Mice damage among ornamental grasses

Are mice having a party among your ornamental grasses?  As UMN Professor and Extension Horticulturist Mary Hockenberry Meyer explains, you can answer this question if you know what to look for.

See what Mary found at the Minnesota Landscape Arboretum Grass Collection in this video.  She'll also talk about what they're doing to manage this problem.

For more "how-to" information, read this article.

Author & Video Producer: Gail Hudson, Extension Horticulture Communications Specialist

Fruit gardening: Frequently Asked Questions of 2018

Growing fruit is rewarding and exciting, but there is also a lot that goes into producing good fruit. Extension Educators Annie Klodd and Jeff Hahn share some of the most common questions they received about growing fruit in 2018.
Why are my apple tree’s leaves wilting and dying in May? Winter injury on apple trees is common in Minnesota. When a tree has been injured by winter temperatures, it is normal for the branches to leaf out in the spring and then wilt, or not leaf out at all. While the affected branches die, the tree will usually still produce fruit since often only a portion of the tree is affected.

Click here for more information on the causes of wilting leaves in apples.
How do I plant a fruit tree orchard? Gardeners, farmers, or organizations aiming to install large plantings of fruit trees should establish a management plan and business plan (if applicable) prior to planting. Fruit is enjoyable to grow and share with others, but these trees are also a significant investme…

How to properly clean your garden tools & pots

Lower the risk for plant disease in next year's garden! Before you store your garden tools for the winter be sure to clean them. Many plant pathogens can survive from one season to the next in infected plant debris, soil, or on tools, trellises, stakes, or pots that were used to grow the plants.
How to clean tools, pots, and other garden suppliesRemove all soil and plant debris attached to tools, trellises, or old pots. Most plant pathogens survive best when sheltered by soil or in plant material. Potting soil, annual plants, leaves and stems killed by frost can all be placed into a compost pile. Use a brush or a hard stream of water from the garden hose to completely remove soil and other organic material.  Disinfectants available to home gardeners1) Bleach (5.25% Sodium hypochlorite)
Make a 10% solution by mixing one part bleach with 9 parts of water. Dip or spray tools with the 10% bleach solution. This will kill fungi, bacteria, and viruses within seconds.

Note: Bleach can be…

Do you sell your fruits and vegetables? If so, here's something you need to know!

Food safety is important for everybody who grows produce. However, if you sell more than $25,000/year (in 2015 dollars), on average, over three years, then you should be aware of a new rule that may apply to you. (Backyard market gardeners and school gardeners—we've got info for you, too!)

It’s called the Produce Safety Rule, and it is one part of the new Food Safety Modernization Act, or FSMA.

Explore World of Squash at the Arboretum!

Want to get into the Fall spirit? This year, visitors to the Minnesota Landscape Arboretum in Chaska can see more than 300 varieties of pumpkins, squash and ornamental gourds. It's a veritable vegetable gardener's paradise!

Should I mulch? Or bag my leaves this fall?

Many homeowners wonder if they should be collecting and removing tree leaves from their lawns prior to mowing, or if the tree leaves can be mulched (mown) into the lawn. Like many recommendations for lawn management decisions, this one can also be answered with the phrase, "it depends."

5 Steps to Put Your Vegetable Garden to Bed for the Winter

What should vegetable gardeners do in October to get the garden all ready for next spring? Annie Klodd recorded a Local Foods College webinar on putting your garden to bed for winter. You can watch the webinar recording at this link.

1) Clean up leftover plant matter   Remove diseased plant material. Either bury it away from the garden, burn it, or dispose of it. Do not leave diseased plant material in the garden if possible, because plant disease pathogens living on those plants can cause future disease problems next year.

If you must leave it in the garden, avoid planting that same type of vegetable in the garden for the next 3 years. For more information, read this article.

If the plants seem healthy (not showing any disease symptoms), they can either be tilled into the garden, chipped and spread on the garden surface, or composted. Large fruit still on the plant, like squash or watermelon that was never picked, can either be chopped finely and tilled into the soil, or removed.
2) …

How to make grasses shine in Autumn gardens!

While many perennials are past their prime by the end of September, landscape grasses are at their peak in the fall, with showy flowers and fall color. Warm season grasses, including miscanthus, big and little bluestem, switchgrass and prairie dropseed are in full flower and tallest height with the warm days of summer and fall. Enjoy the flowers and motion of grasses as they sway in the breeze!
Here's why you shouldn't cut them back! Grasses should not be cut back in the fall. Leave the flowering stems up to enjoy through the winter. Fall cutback may increase the chance of winter injury on grasses and is not recommended for Minnesota gardeners. Birds, bees and other wildlife appreciate the cover of grasses in the winter.
My grasses don't look healthy If you have a grass with few flowers, or shorter plants with dead sections, these are indications that the plant should be divided, a good project for next spring.
If you notice dead or yellow stem on some of your grasses, …

Speckled and spotted but still tasty

Whether you are harvesting from a backyard apple tree or visiting a local orchard, you are likely to find apples that are less than perfect at picking. Don't be dissuaded by appearances. Many of these apples are still quite edible as well as tasty.

There are several different fungal pathogens that infect apple fruit. Diagnosing apple disease problems now can help you make management decisions to reduce disease problems in the future and will help you decide which apples to eat and which to compost.

Is it apple scab? The most common disease of apples in Minnesota is apple scab. Fruit can become infected with the apple scab fungus throughout the growing season. Infections are rough corky spots on the surface of the fruit that are tan to black in color. Scab spots may be small and round or many spots may merge together to form large rough patches on the fruit.

The apple scab fungus does not rot the fruit but if infection occurs when the fruit is young and still growing, fruit may bec…

Check your houseplants now for insect problems

With fall just around the corner, now is a good time to examine your houseplants, those that were outdoors as well as those that stayed inside, for the presence of insect pests. The sooner insects are discovered, the easier it will be to control them.

What to look for  Any insects that are missed will continue to feed and can spread to other plants. Keep plants with insect problems isolated from uninfested ones until the pests are eliminated.

Most of these insects are small and a hand lens is often helpful in detecting their presence. Check leaves, both the top and the bottom, as well as stems, and remove plant debris from the soil surface where insects may reside. You can also use sticky traps to help detect flying insects, like thrips.

Also, look for evidence of insect feeding, such as discolored leaves, webbing or honeydew (a shiny, sticky substance secreted by some insects). Check under the bottom and along the rim of each container as well, and remove webbing or egg masse…

Can I eat that strange looking squash?

What does it mean when squash and melons have scabs, rings, and sunken spots?
The long awaited harvest of melons and winter squash has arrived in Minnesota. Many gardeners are surprised to find sunken spots, rings, unusual color patterns, or raised corky scabs on the fruit. What caused all of these unusual spots and can the fruit be eaten?
Fruit spots can be caused by a number of different factors including fungal and viral plant pathogens. Melons, cucumbers, winter squash, and summer squash are all in the same plant family, the Cucurbitaceae. As a result, these crops often suffer from the same plant disease problems. Although many of the vine crops share disease problems, how severe the disease problem becomes varies by crop and by variety. Below are a few common disease problems found on melons and squash at harvest in Minnesota. Mosaic viruses Several different mosaic viruses can infect squash and melon in Minnesota. Viruses may be spread by insects like aphids or cucumber beetle…