Yard and Garden News

Just in time for the growing season, new information about caterpillars is now available on the University of Minnesota Extension Insect web site. Entitled Caterpillars on ornamental plants, this page discusses how to identify caterpillars, their biology, the kind of injury they cause, and their management.

There are 15 specific caterpillars described, divided into one of four categories: Non-web building caterpillars on trees and shrubs; Web building caterpillars on trees and shrubs; Large, showy caterpillars; and Caterpillars on perennials and annuals.

Each of the 15 caterpillars is described in detail explaining how to recognize them, their favorite
plants, their life history, and their feeding damage. This site is lavishly illustrated with 47 pictures to help identify the caterpillars and their feeding.

Next time you need help with a caterpillar in your yard and garden, don’t forget Caterpillars on ornamental plants!

Author: Jeff Hahn, Extension Entomologist

As we enjoy spring, we seek outdoor activities to not only embrace the pleasant weather but to also help relieve some of the stress of being sequestered at home. Unfortunately with spring also comes ticks. Not to worry, with a few precautions, you can still enjoy the outdoors and protect yourself from these eight-legged pests.
How to ID your tick The two most common ticks in Minnesota are the blacklegged tick (formerly called deer tick) and the American dog tick (also called wood tick). Both ticks are nuisances because they bite us for our blood. More scarily, they can also carry diseases which they can transmit to us.

By far, the blacklegged (deer) tick is the most important disease carrier in Minnesota. This tick is responsible for giving us Lyme disease. From 2010 – 2018, there have been over 10,500 reported cases of Lyme disease in Minnesota. Blacklegged ticks can also vector lesser known diseases such as anaplasomosis, babesiosis, and Powassan encephalitis.

Fortunate…

As gardeners return to their gardens this spring and start preparing it for summer’s plants, they unearth all kinds of insects and other arthropods. One arthropod people have been encountering has been soil centipedes. Because they don’t recognize them, people have questioned if they are pests. Unfamiliar
yes, but pests definitely not.

You can recognize all centipedes from their flattened bodies, their long conspicuous antennae, and their 15 or more pairs of legs (interestingly it is always an odd number). There is just one pair of legs per body segment (compared to millipedes, which have two pairs of legs per body segment) and they are typically
quick moving.

In general, centipedes are found in moist areas, such as leaf litter and mulch and under objects such as stones and logs where they are predators mostly on small insects and other arthropods.

Soil centipedes are common but because they live in the soil, they are normally not noticed. They are often brownish and are slend…

Gardeners across Minnesota have been starting seedlings at home. While we hope your seedlings are healthy and vigorous, some of you are likely seeing some common problems such as seedling collapse, or tall, spindly plants. This guide is meant to help you troubleshoot issues.
Not enough light Are your seedlings looking leggy? This is the term used for seedlings with very long, skinny stems. “Legginess” in seedlings is caused by low light, one of the most common problems when starting seeds at home.

Eventually this will result in weak stems, and the plant will struggle to support itself. If you have a sunnier window, consider moving your plants there. Otherwise you may need to include artificial lights. If you have artificial lights already, try moving them closer to the plants.
Too much water This is another common issue with seedlings grown at home. The seedlings in the photo below are tipping over from the top; a condition known as epinasty. When your soil is water-logged it become…

I don’t know about you—but by the spring, I am hankering for my own fresh, homegrown vegetables!  That’s a summertime thing you say? As brief as spring can be in Minnesota and our region, you can still grow cool season crops with success. 

In fact, you know how warm the sun feels right now?  You can take advantage of it—even warm the soil up to get seeds and transplants off to a good start—we’ll tell you how in a just a bit.

This is Part 2 of our "Yard to Table" series of articles that will help you get growing—even if you’ve never planted seeds before!  You’ll find tips and resources here, and a place to ask your questions, too. That’s what we’re here for! 
What are cool season crops? When it comes to growing vegetables, these are crops that do well when the weather is still cool and spring-like, the soil is cool or sometimes will grow better when they’re partly shaded.  Many plants prefer certain soil temperatures and if conditions are right, they’ll germinate better and fast…

With our screen time now being ALL time, many people are looking for credible online gardening and horticulture resources. Here is a list of my favorites:
UMN Extension videos Watch lots of informational videos on everything from seed starting to our 3-part series on how to pick the right place for the right plant. Tune into the University of Minnesota Extension's Yard and Garden YouTube channel!

Interested in learning more about growing fruit? Here are some of Extension's YouTube videos you might be interested in.  You can also check out our general UMN Extension videos.
MN State Horticultural Society The Minnesota State Horticultural Society is one of the oldest horticulture societies in the U.S. Their Northern Gardening magazine is a great resource and this link provides a long list of information that is online. More benefits with membership, but you can join free, upcoming webinars (next one is April 23rd) on favorite perennials.
Minnesota Landscape Arboretum Check out t…

I receive about 12 calls, texts, and emails throughout the year from grape growers who have spotted an alarming and somewhat disconcerting anomaly on their grapevines.

The question usually goes something like this: "Hello Annie, I have found these weird finger-looking things growing out of my vines. What are these? Are they a problem?"

These long, skinny red structures, which grow from the trunks or limbs (cordons) of the vines are called grape aerial roots.

Why is my vine producing grape aerial roots? Grape aerial roots, in themselves, are harmless. There is no evidence suggesting that they will impact the health or fruit production of the vine. However, grape aerial roots may actually be a sign from the vine that it is stressed or that it has experienced injury in the recent past.

Eric Stafne, a horticulture professor at Mississippi State University, has written an eXtension article describing aerial roots. He explains that while the causes of aerial roots are not thorough…

A common question now is what should be done about any old wasp nests that survived from last year. The good news is not a thing! Whether the nests are hanging from a tree, in a wall void in your home, or in the ground, there are no live yellowjackets remaining in them. To understand why this is so, we need to look at yellowjacket biology

Yellowjackets have an annual life cycle; nests survive for just one season. At this time of year, the only yellowjackets from last season are new queens, which have spent the winter in protected sites, like under loose bark or cracks and spaces in a building.

Once temperatures warm up in the spring, these queens become active and start searching for places to build their nests, typically somewhere quiet and protected. They feed themselves and forage for sources of wood, which they make into a paper mache like material for constructing nests.

Once nests are large enough, queens lay eggs, which develop into workers (sterile females). These w…

Q: I know apple trees require two cultivars to cross pollinate and produce fruit. However, my trees haven't produced apples even though they have bloomed prolifically. Are my trees compatible for cross-pollinating? A:My friend, Jeanie in Montgomery, MN, is an avid, knowledgeable gardener with acres of land planted for bees.

She grows a selection of dwarf / semi-dwarf apple trees: Honeycrisp, Honeygold, Haralson, and Whitney crab. Her 4-year old trees have flowered very well the past two years, but haven't produced much in the way of fruit. She contacted me wondering about tree compatibility and their bloom time.
I went to the best resource: our U of MN fruit breeder and apple expert, Dr. Jim Luby. Here's what he had to say about cross pollination of apple trees:
I tell people not to worry about this in MN. We don't encounter issues in our breeding program as we do our pollinations every spring [in the research orchards].

Genetic cross compatibility and overlap in the time…