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Showing posts from March, 2016

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Giving you easy access to information that will help you to care for your garden and yard is important to us. We're conducting research that will help us gain a better understanding of how the Extension website should be organized, so that it's easier to use. If you'd like to share your opinion, there are two ways to get involved: Complete an online exercise (10-15 minutes) to show us how you would group topics and information.Let us know if you are interested in attending a one-hour, in-person session to test a part of the Extension website that you might use in the future.

What to do about overwintering insects

Jeff Hahn, Extension Entomologist

It is common with the mild temperatures we have experienced recently to see various nuisance insects in homes, especially boxelder bugs, multicolored Asian lady beetles, cluster flies, and western conifer seed bugs. Despite the appearance that they have laid eggs and are hatching now, these insects have actually been in homes since last fall when they first entered structures.

These insects typically took refuge in wall voids, attics, and other nooks and crannies. As long as these areas stayed cold, they remained inactive. However, when temperatures started to warm, they 'woke up' and moved towards warmth, i.e. into the inside of your home. As we are getting into spring, we are seeing this occur more frequently.

These insects often congregate together in clusters in these harborages so as these areas warm up, not all of the insects become active at the same time. Or these insect could be in different places in homes that warm up at di…

Watch out for ticks during April

Jeff Hahn, Extension Entomologist

We enjoyed a very mild March and are anticipating this weather to continue into April. As people get outside more, an old “friend” will be waiting for us: ticks! Ticks are probably the last things on our minds but in fact ticks have been active during March and people have already reported finding ticks on themselves and on their dogs. This is not too surprising as blacklegged ticks, formerly known as 
deer ticks, can be active in temperatures as cold as the mid 30’s (F). Blacklegged ticks are the species that can transmit Lyme disease as well as several other diseases.                   

What does this mean for us? Definitely get outside and enjoy the warm weather when we have nice days. Keep in the back of your mind that ticks could be encountered, especially when you are in habitats where ticks can be common. This includes grassy, brushy, and wooded areas. Minimally check yourself to detect any ticks you may have brought home with you. …

New! Upper midwest home garden care calendar

Timing can be critical to successful gardening. Wondering when you should sow seeds? Plant perennials? Fertilize your flowers? The Upper Midwest sustainable home garden care calendar provides provides best and second-best timing for tasks common to gardens in Minnesota and surrounding states. After consulting the calendar, follow up with U of M Extension publications about your particular plant or garden issue. For lawns, visit the Upper Midwest sustainable lawn care calendar.

Lack of Flowers

Lack of Flowers Mary H. Meyer, Professor and Extension Horticulturist, University of Minnesota
Large flower buds on 'Merrill' magnolia
Why didn’t my peony, forsythia, lilac, tulips, hydrangea, apple tree bloom? This common garden question has no one simple answer. There are many plants and many reasons for a lack of flowers. Listed below are popular flowering plants and common reasons for lack of flowers.
Peony: Recently transplanted or planted too deep is the most common reason peonies fail to flower. Peony buds need exposure to cool temperatures, which buds normally get when planted 1.5 inches below the soil surface…any deeper and flower buds may not get cold enough. When moving peonies, pay close attention to bud height and plant at the same depth. Another reason: If your newly divided peony does not flower, they may need to grow larger before buds develop. Also, see Consider the Site information below.
Forsythia: Flower buds may be killed due to cold temperatures…in MN onl…

Is Spring 2016 a repeat of Spring 2012?

K. Foord, UMN Extension Educator

The warm temperatures encountered in the first half of March of 2016 are reminiscent of the extreme early spring encountered in 2012. However, if you compare this year’s spring temperatures with the 30 year average, we are above average but nothing like 2012.

One way to compare temperature data among years is to create a statistic called a Heating Degree Day (HDD). This number is created by taking the average temperature for the day and subtracting 65 degrees.  The average temperature for the Twin Cities yesterday March 21st was 41 degrees, and thus the HDD was (41-65 = -24).  The idea being that in that day the heat required providing for the 24 degree difference between the 65 degree reference building temperature and the 41 degree average outside temperature was 24. So the HDD for March 21, 2016 was 24. The 30 year normal for March 21st is 35 F, so the HDD for the average is -30. If we sum these numbers for all the days in a month then we can compar…

Prevent Oak Wilt

M. Grabowski,  UMN Extension Educator

It is no longer safe to prune oak trees in Minnesota. Any pruning cuts or wounds made at this time have some risk of becoming infected with oak wilt. This risk will only increase as the weather becomes warmer. Gardeners should avoid pruning or wounding oak trees at this time. If pruning is absolutely necessary, the pruning cut should be covered with shellac or a water-based paint immediately after making the pruning cut.

Oak wilt is a fungal disease that kills thousands of oak trees each year. Red oaks can wilt and die within a few weeks of infection, whereas bur and white oaks may survive several years before succumbing to the disease.

The fungus that causes oak wilt produces sweet smelling mats of fungal spores under the bark of recently killed red oak trees. Sap feeding beetles are attracted to the sweet smell and become covered in spores when they visit the fungal mats. These beetles are also attracted to fresh pruning cuts or wounds on oak t…

Pruning Shrubs for Maximum Bloom

Kathy Zuzek, UMN Extension Educator

Late winter and very early spring are common times for shrub pruning.  Remember though that the pruning of shrubs valued for their flowers and/or fruit should be scheduled based on where flower buds are formed:
Most spring-flowering shrubs bloom on the previous year’s stem growth and should be pruned immediately after they bloom. New stem growth will occur in summer along with flower buds that will develop into next year’s bloom.The flowers of shrubs that bloom in summer or fall are from flower buds that formed on the current season’s stem growth. The best time to prune these species is winter or early spring. This will lead to vigorous stem growth in spring and summer that contain flower buds which open in summer and early fall.

Blossoms on: Scientific Name Common Name Previous Year’s Stems Current Year’s Stems Rhododendron azaleas & rhododendrons X Berberis barberry X Diervilla bush-honeysuckle