Oak trees are known around the world for their impressive strength, longevity, and significant ecological roles. These trees can live for hundreds of years, growing into massive, sprawling structures with thick trunks and wide canopies. Their deep roots anchor them firmly into the ground, making them incredibly resilient to strong winds and storms. The “mighty” oak has earned its reputation and is a great shade tree for any landscape.

The strong wood of the oak tree is dense and hard, historically prized for building ships, furniture, and structures that needed to withstand time and the elements. Oak trees also support vast networks of life. A single mature oak can host hundreds of species of insects, birds, fungi, and mammals, acting as a cornerstone of woodland ecosystems. Their combination of physical strength and ecological importance has led to cultural reverence as well.

There are many varieties of oak making it a versatile tree that can be used in different ways in your landscape:

The Bur Oak (Quercus macrocarpa) is a large, broad-canopied tree that can reach heights of 70–100 feet, with a massive trunk and thick, deeply furrowed bark. Its leaves are large and have a somewhat irregular shape. They are highly adaptable, drought-resistant, and tolerant of poor soils and extreme temperatures, making it suitable for more arid and open areas. Its broad canopy also offers excellent shade.

The Pin Oak (Quercus palustris) is more pyramidal in shape, typically growing 60–70 feet tall with a straighter trunk and a more symmetrical form. Its leaves are smaller and more sharply lobed, with deep sinuses and pointed tips. The branches of pin oak are characteristically horizontal to drooping on lower limbs, contributing to its distinctive silhouette. Pin oak is a popular ornamental tree due to its symmetrical form and rapid growth.

The Columnar English Oak (Quercus robur ‘Fastigiata’), is a cultivated variety of the native English oak, prized for its narrow, vertical growth habit. Unlike the broad, spreading canopy of the standard English oak, this cultivar exhibits a tightly upright form, making it ideal for landscapes where space is limited or where a strong vertical element is desired. Typically reaching 50 to 60 feet in height with a spread of only 10 to 15 feet, the Columnar English Oak is well-suited to urban settings, avenues, or formal gardens. This tree is hardy and adaptable, thriving in full sun and tolerating a range of soil conditions. However, like other oaks, it can be susceptible to powdery mildew in damp conditions.

The “Mighty Oak” has been a vital tree culturally, ecologically, and in landscaping for hundreds, even thousands of years and it will be for years to come.

Christensen’s has all these varieties of oak available. Contact your salesperson, or stop through the yard to pick the one that’s right for your project.

You may have heard of the rise in popularity of native perennials, making you wonder, “Why should I plant them?”. Well, there are many reasons! 

Native plants are beneficial to our environment. Not only do they provide habitats and food for insects and animals, but they create a healthier place for us and our communities. Native perennials are excellent pollinators and will fill your garden with beautiful flowers, attracting butterflies, hummingbirds, and more! They are also beneficial because they help reduce noise and carbon pollution! Finally, natives require less water due to being adapted to their native environment, saving you money and time!

One of my favorite Michigan natives is Asclepias tuberosa (Butterflyweed). This plant is beautiful in all seasons. The star of the show is its stunning orange flowers that bloom mid-summer. Fall interest continues with unique seed pods! Not only is this plant beautiful, but it is also food for Monarch Caterpillars. By planting Asclepias Tuberosa, you can rest easy, knowing that you are helping preserve one of the most beautiful, and vulnerable, butterflies in North America. Stop by the perennial lot and check out our Asclepias tuberosa. Look closely and you might see the stunning Monarch caterpillar yourself!

Last, but not least, are the Echinacea purpurea (Purple Coneflower). This plant is native to prairies, meadows and woods, making it a very diverse and easy to grow Coneflower. Its bushy foliage and purple flowers provide interest all summer long. Once the flowers are spent, if not dead headed, they will last well into winter, allowing Finches and other birds to munch on their seeds. Fun Fact: Echinacea comes from the Greek word ‘Echinos’, meaning Hedgehog or sea urchin, describing the flowers’ spiky look. Can you see the similarity to the hedgehog in your email?

(Note: Although we do carry many Michigan native plants at Christensen’s there are many more that can be special ordered! Don’t hesitate to inquire about natives and we will do our best to get you what you need!)

Choosing a spreading Juniper can be a daunting task. There are so many to choose from and so many factors to consider. Height, width, color, and overall look varies between each variety. There are several varieties that are considered spreading but can end up being taller than some upright evergreen shrubs! So, how do you choose the right spreading Juniper for your customer’s landscape? While that task can be easier said than done, here are a few tips that may help point you in the right direction!

Juniperus conferta ‘Blue Pacific’

Blue Pacific Juniper is a great option when you are looking for something similar to a ground cover. It stays very low to the ground, only getting to be about 1 foot tall, and will spread to be about 6 feet wide. It enjoys full sun, making it a perfect option for open hillsides and sun gardens. Blue Pacific Juniper has blue-green foliage that will surely add interest to any landscape. Or, if you are looking for a similar plant, but in yellow, take a look at Golden Pacific Juniper. It grows the same, but has bright yellow-green foliage instead.

Juniperus virginiana ‘Grey Owl’

Grey Owl Juniper is another great option to consider when deciding between varieties. It will get a little bit taller, growing to be about 3 feet tall and 6 feet wide. It has a unique gray-green color to its foliage. Because it can withstand full sun, it’s a great option for landscapes with minimal shade.

Juniperus chinensis ‘Sea Green’

Sea Green Juniper is known for its vibrant green color all year long. At full maturity, Sea Greens can reach up to 6’ tall and 8’ wide, making it taller than most spreading junipers. Like the others, it enjoys full sun. Because Sea Greens tend to grow faster than other junipers, they are a perfect choice if you want the new landscape to fill in quickly!

Those are just a few of the options to consider.  If those aren’t quite the Juniper you were looking for, visit the Christensen’s plant yard to view what we have in stock.  Your sales person can also advise you on what can be ordered.

Why Tarping Bulk Material Matters

Keeping your load secure isn't just about safety.

It's the law! (MCL - Section 257.720)

Pruning is a powerful tool that can significantly impact how a tree grows and develops. Japanese Maple are elegant ornamental trees that can be delicate and require pruning to maintain an ideal shape. Pruning can alter growth patterns, improve structural development, and reallocate resources. It encourages vigorous, healthy new growth and contributes to the long-term well-being of the tree. However, it’s important to apply the right techniques and timing to ensure that the benefits are fully realized and that the tree continues to thrive.

Japanese Maples can be a significant investment for your clients and providing pruning maintenance to them can be a way to set your business apart. Just be sure you are prepared for the task, with knowledge, and with sharp shears!

Spring in Michigan is always a temperamental time. One day it’s sunny and 70, and the next day it’s snowing. Drop the words “frost free date” anywhere in a Google search and you can get the average date predicting when it’s safe to plant.  The problem with averages is that they come from data on both sides of the average and using this date could leave you frost-burnt as frequently as half the years.

Here at Christensen’s, the full moon in May, or the ‘Flower Moon’ is something we always keep top of mind along with the average frost-free dates. Each spring, we take out our calendars, look for this ever-changing date, and wait patiently. The reason being is that many in our nursery believe that until we are past this milestone, we are still at risk of a frost. Sometimes we get lucky, and this turning point is early, and in other years- like this one, it is late.

The full moon in May was named, as other monthly moons were, by Native American tribes. In regions that were covered in carpets of flowers, the commonly used name of Flower Moon was coined. Other Native American cultures used different names based on what was occurring around them at that time such as Corn Planting moon or Blossom moon. This full moon paired with a clear night has long been believed to bring bitterly cold and unseasonable weather with the threat of hard frosts. The best example of this was the 2020 Flower Moon which brought a cold snap that extended for several days.

Depending on your source, some people believe the Flower Moon is a strong indicator, while others believe it is a long-held myth.  While researching we contacted our favorite local source for all things horticulture, Michigan State University, and asked if they knew of any scientific source that could prove or disprove the moon’s effect on frost. One response was that there isn’t much research on the connection.  Another thought is that it is likely a timing thing – which leads to conclusions that may or may not be able to be proven.

Whether you believe in the Flower Moon or not, we can all agree that, for us in the horticulture industry, a sudden burst of cold weather can be very bad news.  It is dangerous to fresh foliage, buds, and flowering trees.

As you probably know, plants spend the winter in a sleep called dormancy. This dormant period naturally hardens off your shrubs and perennials to withstand the harsh winter temperatures. However, once your plants start to emerge in the spring, we become concerned about colder temps. There are 3 types of freezes issued by the National Weather Service- Frost, freeze, and hard freeze. A frost- sometimes called ‘Killing Frost’ is just frozen dew. Water on the ground, and on the leaves of plants become frozen when temps fall into mid-30s, and winds are calm. A freeze is when temps are at 32 degrees and conditions such as wind prevent the formation of frost. Lastly, a hard freeze is the most serious and occurs when temps drop below 28 degrees for an extended period. It is worth noting that the length of freeze overnight matters. A 1-hour freeze before sunrise is not as worrying as an hours long freeze in the middle of the night. All types of freeze warnings must be recognized, and a plan of action set in place.

The Flower Moon this year is late and will not occur until May 23^rd. If you pair the Flower Moon with the averages that range from May 23^rd to May 27^th, depending on where you are, you will want to watch low temperatures and come up with a plan to combat the frost. Houseplants or potted material can easily be moved inside and out of the cold. In a nursery setting, or in your customers’ yards, here are some tips to mitigate some potential frost damage. At the nursery, we do two main things to battle against frost. Our first method is the continuous running of our irrigation. This frost protection program starts in the wee hours of the morning and runs every 45 minutes for 5-minute spurts throughout the entire nursery. This protects plants by using the heat of the water to continuously warm the plants. Our second mode of action is to use frost protection blankets. These blankets are typically lightweight but effective and do a nice job of keeping the frost from hitting the newly flushed leaves and buds. This method is less practical when talking about protecting an entire nursery, but a very effective plan for flower beds, or to cover smaller groups of our flushed perennials, and Roses. Tucking our plants in before a cold night gives us the peace of mind that they are safe and sound. Some other methods used across the industry are frost fans, under tree sprinklers, keeping grass short to absorb heat, frost protection sprays, and even the use of helicopters to increase air movement.

No matter how you slice it, frost is the arch nemesis of the nursery and homeowners alike. During early spring, it is imperative that we be on watch for cold temps and potential freezes. Whether you can run continuous irrigation, or just plan on using a frost blanket, having a game plan to protect your plants is imperative. Until Memorial Day, we will be keeping our eye on the sky to ensure the best plant material possible!

A special thank you to Michigan State University’s Rebecca Finneran and Keith Mason for help with frost-free dates. MSU is an excellent source for questions on lawns, landscape, gardening and horticulture in general.  You can contact them 24/7 by clicking here. Also, check out MSU’s Enviroweather Tool by clicking here. 

/ˌrōdəˈdendrən/
     noun

First of all, “Rhodys”, Azaleas, and ‘PJMs’ are all the same!!! They are all officially part of the rhododendron genus. They are one of our most popular stars of spring. All of those stocked at Christensen’s are Broadleaf Evergreens, flower in the spring, stay leafed out all year, and start the process over again. (We do not stock deciduous Azaleas anymore but if you need them, we will get you some.)

I also like ‘Boursault’, again another purple flower (heading towards pink). ‘Boursault’ is a Rhododendron catawbiense hybrid and is short. It will reach 5-6’ max. Both are those hardier H1 hybrids.

Last on my list of Rhododendrons is the small-leafed “PJM”. ( FYI: PJM is a series developed by Peter J. Mezitt and his son in the 1930s to be exceptionally winter hardy.) They are getting very hard to find. Sometimes we get ‘PJM’, ‘PJM Elite’, or ‘PJM Regal’. They are all very similar and can work interchangeably. All have the same ‘PJM’ flowers and will reach 3-5’.

In late fall, besides the trees changing colors, you will also notice a change in your perennials. In this article, I would like to discuss fall perennial practices. Topics will include fall cleanup, which perennials should be cut back vs. which should not, perennial varieties that provide habitat for local wildlife, and how we close up the perennial greenhouses in the nursery. These tips should help with the overwintering process.

On the flip side, there are a few arguments for leaving some perennials in your garden alone. To protect the habitats of birds, and beneficial insects, you could consider not cutting Rudbeckia, Echinacea, Eupatorium or perennial sunflower. These seeds will provide food throughout the winter. If your home is close to wooded areas, meadows, or contains a brush pile, your garden may be even more habitat friendly. Some perennials that I would not cut back in the fall would be Asclepias, Ferns, Heuchera, and Dianthus. This is to protect the crowns during the harsh winter. Perennials are more cold-hardy when their stems are left intact. These stems can trap in snow, and work as an insulator for their crowns. A quick clean-up in the spring, and these will be just fine. The last reason why I would consider leaving some perennials be, would be their winter interest. Some stuff just looks awesome covered in snow! Species with stiff stems, or flat or cone-shaped dried flowers have a great winter look! Things like Sedum Autumn Joy, Ornamental grasses, or Echinacea Purpurea add to a garden’s winter beauty!

It is also not uncommon to line an entire house with some of those winter tolerant varieties to both save space, and act as a buffer for other material. We also have one heated structure that we use to protect our grasses (mainly Miscanthus, and Pennisetum varieties), from ever freezing. By keeping minimum heat on our grasses, we are ensuring a healthy, happy grass come spring.

Whether you are overwintering perennials in your landscape, or at your nursery there are many factors to consider. Moisture, temperature, snowfall, and sometimes just plain old luck are all factors that will determine how your perennials fare over a long winter. Keeping in mind potential winter damage, bird and insect benefits, and most importantly, what’s best for the plant, will ensure a seamless transition to the brisk winter days! Happy spring clean ups!

Marketing is like magic. Magic is all about misdirection and sleight of hand. The performer will have you so focused on what the left hand is doing so that you never notice the right foot. Marketing can be very similar, focus on the positive and redirect from the negative. Everybody, I’m sure, remembers the expandable garden hose craze. For $25, they were great! Until you got 1 teeny tiny little hole, but nobody mentioned that the stretching feature comes at a cost of durability. Concrete wall and pavers are in the same boat, they have been advertised and promoted as low maintenance, especially compared to traditional wood decks. But what does that really mean, low maintenance? Let me redirect your focus over here then.

‘Low’ does not mean ‘none’. And, that does not always mean quick and easy, either. Concrete is a sponge; its pores will trap all sorts of dirt and debris. Rusty water, red soda stains, tree sap and salt residue are just a few examples of what your concrete products can soak up. This does not affect the strength or longevity of the brick but it sure can alter the color and appearance of it. To bring it back to almost a new appearance you will need to wash it!

So how does one wash a brick? It does not involve any toothbrushes or mops, but it does involve some specialized cleaners depending on the stain or material you are trying to wash away. Not all, but most chemical cleaners have some small amount of acids in them, this is why you rarely need to scrub the concrete. The cleaner is designed to either soften or dissolve the materials, then simply rinse away with a garden hose. But with that dissolving effect comes a warning, left for too long or too strong of a mix could start to dissolve the concrete’s smaller particles which will leave the concrete pitted and appear much more aged. Always test on a small obscure place on the concrete to test the effects. There are cleaners that specialize in gum, oil, tar, rust, and organic material like food condiments and popsicle drippings.

After the cleaning, you now have an opportunity to seal the concrete, if you so desire. Years and years ago you would have to wait 6 months to a year for the efflorescence to work its way out of the concrete. Back then the sealers were not breathable, they trapped everything in. Now they have water based breathable sealers that can be applied shortly after installation. But why would one want to seal the concrete, especially if you can simply clean it? Think of sealer like shoe shine, it helps protect the shoe’s material while it helps to improve the appearance. It will make cleaning stains much easier as well as help maintain or enhance the color of the concrete. This could be very important around cooking and dining areas. You don’t have to seal every year, maybe not even every other year, but you will have to reapply again at some point to maintain the same protection and appearance.

Sealing can be both a blessing and a curse. It is so nice to take the hose to a grape jelly blob and simply hose it away. But you may have one more thing to add to an ever-growing list of springtime chores. I choose to live dangerously; I go sealer free. But I also have an amazing washing system, a yard full of kids and a hose. The car, house, dog, tree, neighbor kids, and most times the patio get a good washing many times during the summer. But if you do not have a high fructose fueled (kids with popsicles) washing system like me, stop by the Hardscape Center and let us help you make your stains and grime disappear, magically!

I love spring! The trees foliating and flowers blooming, the smell of fresh air in the house, planting the garden, and, of course, the boat rides. Last spring was nice, not hot too soon, no crazy two-foot snowstorms, but we did have a slight amount of extra rainfall. Slight being the understatement of the year, as we had over 2 months’ worth of rain in about a week! So, for a while last year I lived on 2 lakes, one my boat was on and the other in my back yard! Detroit and some neighboring cities were hit especially hard. A combination of old or faulty equipment, the inability of the infrastructure to process that amount of water, and I’m sure some design flaws and errors along the way.

Water is the most destructive force on the planet, and it doesn’t take much of it to do a whole lot of damage. Climate changes have been producing some of the most intense and destructive weather that we have ever seen, and there is no sign of this pattern changing. What once worked before may be inadequate for today’s needs. As many municipalities change their designs on the processing and reclamation of storm and runoff water, should you also change your designs on the landscaping end?

Unfortunately, we suffer every year from the effects of our freeze thaw cycle. The water underneath thaws and refreezes so many times that it creates voids by pushing everything around it away. When it thaws, those voids get refilled yet with more water and the process restarts. The problem is that the water has nowhere to go. You can’t stop the expansion, but you can give it a path to follow. One of the newer trends has been the use of clean fill aggregate as a base for driveways, patios, and even roads.

The biggest differences between the clean aggregates and the traditional is the removal of the finer particulates and a more consistently sized stone. The lack of the finer particulates does not take away from the strength and stability of the base, but it allows for water expansion without exerting outward pressure in a confined area. This also allows for excellent drainage, so no more puddles or ponds. Many municipalities have incorporated this type of base because of how effective it is in reducing icing and refreezing since the water drains as soon as it has thawed. And the best part is you do not have to use a permeable style paver to obtain the benefits of a permeable base. The cost to change from traditional to permeable is negligible, the installation is slightly different but easy to follow.

As great as this sounds, there are of course a few draw backs. Firstly, is finding the material. Permeable pavers and permeable materials are slowly becoming more popular, but you may find certain areas more challenging than others to find the supplies you need. You will have to retrain your crew for a new installation process which is not hard, but change can always be a challenge. Lastly, this base requires maintenance. If you think of the base as a sponge, when the top is covered and clogged it no longer absorbs as well. Depending on the area, the amount of traffic, and surrounding landscape, this may need some frequent attention or very minimal maintenance. So, keep in mind that a permeable based driveway might not be the best choice if you live off a dirt road. But if your sunny backyard patio is always underwater after a good rain, that might be helpful choice.

At Christensen’s Plant and Hardscape Centers, we stock a huge assortment of drainage components from companies like NDS. We also stock the clean aggregates for the Hardscapers out there, too. Stop in and see what we can help solve for you. I promise you; it will not put a drain on us!