Category Archives: Yard & Garden Notes

Fall is for Planting

September 4, 2010 – 8:08 am

While improved growing, packaging and planting techniques now enable us to be successfully planting from April through November, many people think of fall as an excellent time for planting a wide variety of landscape plants, and with good reason.

There are a number of things that make fall planting appealing.  Temperatures are cooler, so working conditions are more pleasant for most people.  Shorter days and longer nights mean plants use less water, making the watering of new plantings a bit easier.

Weed germination is less in fall, so maintenance needs are reduced for fall planting, and when fall rains come, soils stay soft for easy digging for a longer period of time than in mid-summer.

Probably the biggest advantage to fall planting is the cost savings.  Most nurseries have reduced prices on many items, so excellent bargains are available.  Don’t delay too long in securing your desired plant materials since inventories tend to be thinner as the seasons gets closer to November.

Enjoy your time in the autumn garden.  These can be some the most pleasant days of the whole year to enjoy the outsdoors and your cherished gardens.

I have also shared this post with the Northfield News.

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By Leif Knecht | Also posted in Retail Sales | Comments (0)

‘Fox Valley’ Dwarf River Birch

September 2, 2010 – 6:21 am

‘Fox Valley’ Dwarf River Birch – Betula Nigra – Over the years many people have admired the beautiful cinnamon color peeling bark of the River Birch.  Handsome as both a single stem, or clump, this Minnesota native has been a staple of beautiful landscapes. 

One difficulty with normal River Birch has been that they are sometimes too large for smaller areas of our landscapes.  Fox Valley Dwarf River Birch solves this problem with a mature size rating of 12′ tall by 12′ wide.  Fox Valley sports an interesting bark similar to regular River Birch, can handle damp soils, and can be used as a focal point around which to artfully group shrubs and perennials.

The ‘Fox Valley’ Dwarf River Birch prefers neutral to acidic soils, and with just a bit of supplemental watering, can prosper in upland soil.  Check out this new and interesting birch for small spaces.  

I have also shared this post with the Northfield News.

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By Leif Knecht | Also posted in Retail Sales, Trees | Comments (0)

Hydrangea Trees

August 30, 2010 – 7:03 am

Have you noticed here and there the beautiful white (and pink) blossoms on small (4′-9′ tall) trees over the last 5-6 weeks?  You have probably been admiring the lovely mid to late summer blossoms of the hardy hydrangea trees.

The whole paniculata family of hydrangeas are exceptionally cold hardy, and are useful in the landscapes in both shrub form and also when carefully trained into small trees.

My wife and I are frequent visitors to the Boundary Waters Canoe Area Wilderness, which takes up to Ely, MN on a regular basis.  I gained an awful lot of respect for hardy hydrangea trees when I noticed several large specimens growing in the front yards of homes in Ely, where -40 degrees temperatures occur almost every winter, and sometimes as low as -55 degrees.   The trees were in full bloom in late July to late August and had to be 30-50 years old or more, judging from the trunks that were up to 6″ in diameter!

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By Leif Knecht | Also posted in Landscaping, Retail Sales | Comments (0)

Dakota Pinnacle Birch

June 24, 2010 – 7:14 am

Dakota Pinnacle Birch is beginning to make a statement in landscapes across the Upper Midwest.  Slender and upright in it’s form, and very uniform in growth habit, Dakota Pinnacle Birch is extremely hardy, thriving in climate zones 3 to 7 and tolerant of many soil types including those with alkaline pH.  Growing quickly to a mature size of 30′-35′ tall by 8′-10′ wide, Pinnacle becomes an eye catching feature of the landscape as its bark changes from brown in youth to a striking white.

This nice hybrid birch can serve as a focal point specimen tree, or being clumped with 3-5 trees close together, or in a grove of randomly scattered individuals.  It is a perfect tree for narrower spaces where you want a tree, but a larger one just won’t work.   In just 3 to 5 years, a modest sized Dakota Pinnacle Birch will develop into a lovely tree.  Pinnacle has been touted as having better resistance to birch borer than other white bark birch varieties, but we still recommend a once a year, one minute treatment with the systemic insecticide, Imidacloprid.  Imidacloprid is now widely available under a variety of name brand labels. It’s very easy to apply.  Pour a few ounces in a 5 gallon pail, add a couple of gallons of water, and pour the solution onto the soil within 12 inches of the trunk.  The tree roots will absorb the protection and send it throughout the tree.

We gave Dakota Pinnacle Birch available in containers – single stem and some in clump form.

I have also shared my blog here with the Northfield News.

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By Leif Knecht | Also posted in Retail Sales, Trees | Comments (2)

Air Pruning Nursery Pots

May 4, 2010 – 3:08 pm

Air pruning nursery pots produce trees and shrubs with better root systems.  Here at Knecht’s Nurseries and Landscaping we have been using air pruning pots for several years to avoid producing trees that are root bound.

This simple technology of having dozens of air pruning openings built into the design of a molded plastic nursery pot prevents root circling inside the pot.  The result is a well balanced, properly shaped fibrous root system that prevents trees from becoming root bound. 

When you plant trees and shrubs produced with an almost perfectly formed and vigorous root system, the trees become established very quickly following planting on your property, and as a result are healthier and grow more quickly than trees that have been grown in traditional plastic nursery pots.

Chris Siems of Northfield who has a web blog -  Oak-Watch.blogspot, did a segment on Ron Schara’s Minnesota Bound shown on KARE 11 May 2nd showing the benefit of Oak trees and also discussed the benefits of air pruning nursery pots.   We have over 2000 potted trees available here at the nursery that are produced using these air pruning nursery pots.  Stop in soon to see the difference in this better growing technique.

I have also shared my post here with the Northfield News for their blog section.

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By Leif Knecht | Also posted in How To Advice, Trees | Comments (0)

Planting Annuals

April 30, 2010 – 6:27 am

Much warmer than normal March and April weather has many of us eager to be in the garden, and get some annual flowers and vegetables planted.  It should be safe to plant cool season annuals such as pansies, snapdragons, dusty miller, dianthus, alyssum and petunias  as well as veggies such as cabbage, potatoes, spinach, radishes, lettuce, onions, broccoli, and cauliflower.

The planting of warm season annuals such as impatiens, begonias, salvia, marigolds, bacopa, celosia,  ageratum, coleus, and tender vines among others should wait until after Mother’s Day or even until after May 15th, which is the average date of the last frost in the Northfield area.  The same goes for warm season veggies such as tomatoes, peppers and the vine veggies – like cucumbers and zucchini.    You really lose very little by waiting.  If warm season plants go in too early, they may stress out and not produce as well in mid to late summer.

The planting of trees, shrubs and most perennials should be just fine now, since the vast majority of them actually prosper in cool spring weather.  Be patient and ‘Happy Planting.’

You will also find this post in the Northfield News’  blog.

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By Leif Knecht | Also posted in Annuals, How To Advice | Comments (0)

Red Maples are Blossoming

April 5, 2010 – 5:25 pm

We normally think of beautiful spring flowers as crocus, tulips, daffodils, flowering crabs, magnolias, plums, cherries and redbuds.  One of my spring favorites is often overlooked.

Red Maple trees (Acer rubrum) quietly put on a wonderful show of beautiful red flowers each spring, long before their leaves emerge.  Preferring mildly to strongly acidic soil, Red Maple trees and their popular hybrids push out early spring flowers that cover the canopy of the trees in a beautiful mantle of lacy red.

The spring color show generally lasts for one to two weeks, and depending on the way spring weather breaks, can begin at the end of March or as late as mid-April.  Take time this early spring to enjoy the show put on by rubrum maples.  The lovely spring color is a good reminder of the fantastic fall colors of yellow, orange, red and magenta that Red Maples give us every autumn.

 I have also blogged this article on the Northfield News website.

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By Leif Knecht | Also posted in Landscaping, Trees | Comments (0)

Transplanting Trees and Shrubs

April 5, 2010 – 5:21 pm

Spring tree harvest is under way at the nursery.  This means that if you have been thinking about moving some trees or shrubs around your property, the next 15 or 20 days will be your best opportunity of the year for most varieties.

If you are able to move plants before they leaf out, the buds that swell up after you transplant will send a hormonal signal to the cut roots to begin very rapid growth of tiny new roots out into the surrounding soil.

Make sure to dig your planting holes extra wide so the new roots will have plenty of soft soil through which they can penetrate.  Avoid heavy packing of the soil you fill around your relocated plant.  Waterings and rainfall will settle the soil just fine.

Your plants will be especially happy if you mix some slow release fertilizer into the backfill soil before you bank it in around the roots.  Be sure to plant no deeper than the depth at which the plant was growing in its previous location.  Remember – even though it’s not a “new” plant for you, it has been newly transplanted so you will need to water it all season as if it were a brand new plant. 

You’ll find this blog also posted on the blog post for the Northfield News.

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By Leif Knecht | Also posted in Landscaping, Trees | Comments (0)

It’s a Great Time to Cut Firewood

March 27, 2010 – 8:12 am

This is a great time to cut firewood.  With the early snow melt, and cooler or slightly below freezing nights, it may be possible to get to some of those dead trees you’ve had your eye one.

Even if you can’t drive right to the trees due to soggy ground conditions, you can carry in your saw, gas and a small tool box and enjoy an hour or two of pleasant work dropping and slicing/dicing trees into convenient lengths.  I have always preferred to split the blocks of wood out in the woods before loading.  In this way the mess stays in the woods and I can load, unload and stack lighter pieces of wood, means less effort and less risk of back injuries.

You will get the great benefits of more heat and cleaner burning if you are able to dry your wood for two years prior to use.  By working ahead two to three years, everything about making and using firewood gets easier and more satisfying. 

If you are cutting ash trees, be sure not to move the firewood out of Rice County.  This will be a habit we should all observe from now on to minimize the chances of spreading Emerald Ash Borer to un-infested areas.  While no infestations have been found in Rice County, this new way of handling wood from ash tree should become standard procedure for all of us. Read More »

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By Leif Knecht | Also posted in How To Advice | Comments (0)

Don’t Rush Your Spring Yardwork

March 19, 2010 – 8:14 am

The heavy and deep snowpack we had this winter means there is very little frost in the ground.  Even though it has seemed as if winter will never end, and all the plants will wake up late, we just might see buds swelling at normal or slightly earlier than normal dates since many trees and shrubs will be able to have root systems activate in unfrozen ground. 

The last day or two, I’ve noticed that puddles of melt water were disappearing rapidly.  This also speaks to the large amounts of unfrozen ground beneath of those snowbanks.   Crocuses on southern exposures are now blooming, so spring is right around the corner!

We all are looking out at our lawns that were hidden for so long.  My lawn definitely needs a little TLC once it dries up.  In addition to the light spring raking that we’ll need to do – we have many little mouse tunnels several places in the lawn.  The mice were able to tunnel from place to place underneath the snow this winter and were safe from the predators.  We have one little mouse racetrack off the corner of the house that we will actually need to fill with soil and seed. Read More »

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By Leif Knecht | Also posted in How To Advice | Comments (0)

A Good Time to Prune

March 10, 2010 – 6:35 am

The time period from mid-March to mid-April is especially good for pruning trees.  With no leaves on the trees, it is much easier to evaluate the structure of the tree, choosing weakly attached branches for removal and leaving strongly attached branches to become the permanent framework.  The next month is also a good time for pruning Oaks and Elms, since there is a far lower chance of infection of the pruning cuts to cause Oak Wilt and Dutch Elm disease, than during the warm season from may through mid-October. 

Last April in my Blog Post, I discussed tree pruning — rather than re-writing another post – I am bringing it back this year.  It is so relevant and after a long winter, everyone is anxious to get outside and get something done and pruning your trees might be on your list.  The following is my blog post from April 15th of last year.

During late winter and early spring yards and gardens can often look their worst.  The grass is brown and sometimes damaged by winter stress, pets, de-icing products leaking off sidewalks, driveways and streets, snow plows, squirrels, and even foot traffic.  The tops of perennials that may have provided some winter interest are now tired and faded.  Interesting shrubs, vines and ornamental trees such as Winterberry, Bittersweet, High bush Cranberry, Mtn. Ash and certain flowering crabs that displayed beautiful red fruits all winter long now have finally faded.  Certain evergreen trees and shrubs show ugly browning foliage due to winter burn. Read More »

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By Leif Knecht | Also posted in How To Advice, Landscaping, Shrubs, Trees | Comments (0)

Why some Trees are Changing Color Early

September 16, 2009 – 9:08 am

After a dry early summer and some nice rains in August, a three week dry spell has pulled soil moisture levels back down to levels that are stressful for many plants.  A good soaking with sprinklers or irrigation systems will help reduce stress on landscape plants as they begin the process of going dormant, and increase the likelihood of handling the long winter without damage.

All over town trees are turning color and/or dropping leaves early, while others are still all green.  The reasons are many.  Some varieties of trees such as American Lindens, Boxelder, Ash and Walnut are programmed to shut down their leaves earlier than other kinds of trees, and this early turn gets accelerated even earlier when drought stresses of several consecutive years add up.

Some trees are turning color early because of poor sap flow from the roots to the top of the tree.  Roots that wrap around the trunk of the tree just below ground level press more tightly with each passing year as they grow larger in diameter.  Sap flow to the crown gets more difficult each growing season, and the tree turns color earlier each year.  Eventually certain branches die, and then most of the tree.  Correcting or eliminating these step girdling roots is difficult, but not impossible.  You may want to consult a certified arborist for help. Read More »

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By Leif Knecht | Also posted in Trees | Comments (0)

Summertime Planting Projects

June 29, 2009 – 6:38 am

This is the time of the year when customers often ask us if it is too late to plant trees, shrubs and perennials.  The short answer is a definite – NO IT’S NOT TOO LATE TO PLANT!

Success with summer plantings is easy to achieve.  Trees, shrubs and perennials have the same needs whether it is spring, summer or fall, and following a few simple steps will ensure your success.

Proper planting technique, adequate but not excessive water, adequate but not excessive sunlight, and adequate but not excessive nutrients are all you need to provide your new landscape plants whether it is spring, summer, or fall.  It is just as easy to do in summer as at other times.

When you plant, root prune potted plants aggressively, cutting through matted roots on the outside of the root ball many times on the sides and bottom.  This will allow many new roots to quickly shoot out into the surrounding soil, providing much faster establishment and far better long term vigor.

Plant no deeper than the level the tree, shrub or perennial was growing in the pot or field, and make a circular dike of soil an inch or two high around each plant.  Place 1 to 2 inches of mulch over the dike to keep it from washing away during the first year when the plant is becoming established.

The dike will assure that the small amounts of water you provide everyday or every other day during the first 2-3 months will soak directly down into the root ball, providing adequate, but not excessive moisture.  By making this small dike around each plant, it takes only a few seconds a day to water each plant by hand.  As a result, most planting projects will require only a few minutes a day to keep adequately watered. Read More »

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By Leif Knecht | Also posted in How To Advice, Landscaping, Perennials, Retail Sales, Shrubs, Trees | Comments (0)

Leaf Tatter

June 18, 2009 – 3:27 pm

Leaf tatter on certain varieties of trees has caused them to look as if they are diseased, sick or being attacked by insects.  For the last several weeks I have taken a steady stream of calls about trees that are looking bad.  The calls started coming in a couple of days after we had 2 consecutive days of heavy spring winds in the 40 to 50 mph range.

The good news is that if your tree is suffering from leaf tatter, it is very unlikely the tree will die.  The bad news is that the tree may look bad for the rest of the 2009 growing season, but will come back strong next year.

Leaf tatter occurs when tender spring leaves are abused by heavy winds.  Hour after hour of violent wind creates tiny cracks or tears in the leaves.  A few days later these areas turn black, and later brown and crispy.  Much of the leaf tissue may be alive, but the damaged cells eventually just fall off, leaving a tattered leaf that has holes that might lead you to think insects were chewing holes in the leaves.

Red Maples such as Northwood, Autumn Spire, Red Sunset and Burgundy Belle are the most susceptible to leaf tatter.  Newly planted hybrids of Red Maple and Silver Maple also can be vulnerable to leaf tatter.  Once the hybrids such as Autumn Blaze Maple and Sienna Maple have been established for 2 or 3 growing seasons leaf tatter is much less common.  The trees have grown larger root systems and the larger volume of roots allows the tree to more rapidly thicken the tissue of the leaves to a thickness that is able to resist cracking in heavy winds.

This year the violent winds in mid to late May came from the south/southwest.  If your sad looking tree looks worse on the south side than on the north side, it is probably leaf tatter that caused the damage.

If you see new growth emerging from the tattered areas, and we don’t get bad winds for several weeks, and the new leaves look normal, then the damage your tree experienced was leaf tattering.

To help a tree work past the leaf tatter, water it heavily once a week and fertilize with Miracle Grow once every three weeks.  Apply no fertilizer after August 20th, so the tree can use up the fertilizer and go dormant at the right time in the fall. 

I have also shared this blog with the website at the Northfield News.

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By Leif Knecht | Also posted in How To Advice, Trees | Comments (1)

Summertime Planting

June 17, 2009 – 10:59 am

Summer planting is successful planting.  Long warm days give newly planted trees, shrubs and perennials all the daylight they need to establish new root systems over the remainder of the summer and fall.

Simply provide each plant with adequate, but not excessive moisture and nutrition, and they are sure to follow their internal genetic programming that favors growing new roots over producing lots of top growth.  This will prepare summer plantings to store lots of energy this season for an explosion of growth next spring.

I recommend mixing a moderate amount of timed release fertilizer in with the soil you fill in around each of your new plants.  Mix the fertilizer evenly into the backfill soil and don’t overdo on the amount of fertilizer.  With each watering, the plant will get a wonderful little dose of nutrition.

Two nice rains of almost 2 inches each have come to the Northfield area in the last week and a half, partially alleviating some of the stress that the dry spell of April and May caused for landscape plants, for cops and natural lands.  Keep in mind that sub-soils got extremely dry this spring and that several more substantial rains will be needed to restore moisture reserves to normal.

If long dry spells return in July, August and September, your plants will benefit from a good watering, but for now that won’t be necessary unless you have landscape plants that have been planted during the last 12 months, and are still trying to grow new roots out into the surrounding soil.

I have also shared this post with the Northfield News on their website.

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By Leif Knecht | Also posted in How To Advice, Retail Sales | Comments (0)