Plant Profile: Southern Magnolia (Magnolia grandiflora)

Southern grandeur. The classic Southern tree. The epitome of large plantations. Southern Magnolias. They are adored by virtually all those who grow them and they are the envy of many gardeners who don’t. Their gorgeous evergreen leaves are a favorite for Christmas decorations or any other special occasion that comes along.

Southern Magnolia (Magnolia grandiflora) is native to all of the Deep South states including Texas and its northern range covers parts of Maryland. The ability to grow in such diverse conditions shows that Southern Magnolia is a tough tree. Southern Magnolia needs full sun to do its best, at least in the Mid-Atlantic gardening region. Perhaps in Texas it appreciates a little shade. It isn’t very particular about its soil type, so long as it’s not sitting in standing water. I’ve seen them used in streetscapes with very limited soil and they seem to do fine. In those conditions, they will never be as beautiful as the ones grown in an open area with lots of room to spread their roots, but that’s to be expected.

Southern Magnolia bloom in June and their flowers are simply fantastic. They are the subject of many pictures and paintings, most of which can be found in my Mom’s house…she just loves them. The 6″ to 8″ wide blooms are fragrant but not so much as to be overpowering. They are a vanilla white and persist on the tree for two to three weeks, depending on weather conditions. Here are some pictures of the buds, flowers and the seed pods.

Southern Magnolia
The buds

 

Southern Magnolia
The blooms

 

Southern Magnolia
The spent bloom

 

Southern magnolia
The beginning of the seed pod

 

southern magnoliaThe main drawback to growing Southern Magnolia is that they shed their leaves…right as the trees are flowering. Their thick, shiny green leaves don’t decompose readily and can’t just be chopped up with your lawnmower. This is one of those chores that require you to break out the rake in June. One way to solve this problem is to leave the full skirt on the tree instead of limbing it up. If you leave the skirt intact to the ground, most of the leaves will fall through the tree and remain as mulch for the tree. If you limb it up, you’ll have Magnolia leaves from one end of your property to the other.

There are many cultivars of Southern Magnolia that are available in the trade. Here are some of the most popular:

  1. Bracken’s Brown Beauty‘ – this variety grows from 30′ to 50′ tall by 15′ to 30′ wide versus 50′ to 80’ tall that the straight species can reach.
  2. Edith Bogue‘ – this selection takes a little longer to flower but it boasts two important characteristics: it’s more cold hardy (to Zone 6) and it has a tight pyramidal form.
  3. Little Gem‘ – if you need to squeeze a Southern Magnolia into a smaller space, ‘Little Gem’ is an option. Topping out at 20′ tall x 10′ wide, this is perfect for those more compact landscapes.

 

While all of the literature says that Southern Magnolia is only hardy to Zone 7, try pushing it if you have a warm area in your landscape. There are tons of microclimates within an average garden and you should try to utilize them when you can. Have you grown Southern Magnolia in your landscape? Have you pushed it past Zone 7? Leave me a comment below or shoot me an e-mail. If you enjoy being part of the Mid-Atlantic Gardening community, join our e-mail list (upper right hand corner of this page), become a fan on Facebook and follow me at Twitter. Happy gardening!

 

Did You Know? Ivy in Trees

Today’s post is about ivy in trees. If you look around, you’ll see it everywhere. It seems so innocent as it starts to creep and crawl up your trees. It’s even attractive. But then the crawl turns into a dash and before you know it, the ivy is at the top of your trees and it’s completely out of your reach.

Many people wonder if ivy in trees is really a bad thing. Let me assure you that it is bad…really bad. Let’s look at some of the reasons:

  1. Ivy grows at an almost exponential rate and shades out the foliage of your tree. Without the leaves of the tree photosynthesizing, your tree is a goner.
  2. With its thick growth, ivy also provides great cover for all sorts of pests and diseases that can affect your tree. The ivy also keeps the trunk and stems moist which invites disease all by itself.
  3. Perhaps one of the most overlooked reasons for not allowing ivy to take over your trees is the increased canopy that is susceptible to wind. The ivy acts like a sail on a sailboat and can cause your tree to go down during a summer thunderstorm, or worse, a hurricane.

 

ivy in treesSo what can you if your ivy has already has escaped into your trees? Depending on the size of the vine, you can either try to physically pull the ivy out of the trees or cut the vine near the base of the tree. It’s not a bad idea to do both.  I must warn you that if you cut the vine and leave the remaining ivy in the tree, you won’t kill all of the ivy. Ivy is amazingly tough and has probably rooted into your tree. I don’t mean that it has tapped into the vascular system of the tree like mistletoe does but it has rooted onto the stems and with all of the shade that the ivy provides, there’s still a lot of moisture available to sustain the ivy. Don’t be discouraged…just keep battling the monster once pruning cut at a time.

Another warning: the ivy that is successfully killed by your pruning cuts will turn brown in your tree. It won’t last long but I wanted to warn you that the tree that you’re trying to save will look as though it has died. Take pleasure in seeing the brown ivy; you’re one step closer to an ivy-free tree.

Persistence is the key to eliminating the ivy in your trees. Realize that with every piece of ivy you remove from your tree, your tree is breathing a sigh of relief. If your tree is particularly overgrown with ivy, you may want to consider hiring a Certified Arborist with a bucket truck. They will be able to access much more of the canopy than you can from the ground.

Do you have any experience with ivy in trees? Do you have other methods that you’ve used to successfully remove ivy? Leave me a comment below or e-mail me…I’d love to hear what’s worked for you! If you enjoy being part of the Mid-Atlantic Gardening community, join our e-mail list (upper right hand corner of this page), become a fan on Facebook and follow me at Twitter. Happy gardening!

 

Pests and Diseases: Galls on Trees

I have a white oak (Quercus alba) that lives in my backyard. It’s home to birds and squirrels and galls. Galls on trees are a pretty common occurrence but they can cause great concern to gardeners. Is there really cause for concern? Let’s take a look.

Galls are a growth that occurs on the leaves or branches of trees as a result of a myriad of pests. These pests can include fungi, bacteria and nematodes although the most common are insects and mites. When the insects and/or mites invade the tree, a gall is formed by the tree and the pest is protected inside. The gall also serves as a food source for the pest. For the pest, it’s pretty much a win-win; it’s protected and fed by the gall.

Galls on trees may be unsightly but there really isn’t much need for concern by the gardener. Once the gall has formed it’s going to stick around for a while. No amount of spraying will remove the galls and they don’t take a tremendous amount of energy away from the tree. Consider them an anomaly and let them be. If you are truly concerned about them, consult a Certified Arborist or your local extension agent.

For curiosity’s sake, let’s take a look at some pictures of galls.

galls on trees
Photo courtesy of www.unl.edu

 

galls on trees
Photo courtesy of www.duke.edu
galls on trees
Photo courtesy of www.foxtreeservice.com

 

Do you have any experience with galls on trees? If you’d like to share with the Mid-Atlantic Gardening community leave me a comment below or send me an e-mail. If you enjoy being part of the Mid-Atlantic Gardening community, join our e-mail list (upper right hand corner of this page), become a fan on Facebook and follow me at Twitter. Happy gardening!

Plant Profile: Golden Rain Tree (Koelreuteria paniculata)

golden rain tree
Photo courtesy of www.hort.uconn.edu

Golden rain tree is a delightful small tree with wonderful yellow flowers. It is a showstopper when it’s in bloom as it is now in Virginia. Hailing from China and Korea, golden rain tree grows to 30′ tall by 30′ wide. Make sure that you allow enough room for it to reach its 30′ width because it almost certainly will if left to its own devices.

Golden rain tree has several noteworthy characteristics that make it a desirable tree for your landscape. Let’s take a look at some of these:

THE FOLIAGE: Golden rain tree has pinnate or bipinnate leaves; that’s a fancy way of saying that the leaves are divided and feathery in appearance. The fall color is variable but if you purchase one with good fall color, you’ll be rewarded with yellow foliage.

golden rain tree
Photo courtesy of www.vanderbilt.edu

THE FLOWERS: This is the reason that most people want a golden rain tree in their landscape. The flowers really are quite phenomenal and have great presence in the garden. The yellow color draws your eye to the tree and if placed properly, the blooms can entice a visitor to a desired area of your garden when the tree is flowering. The blooms persist for upwards of a month and carpet the ground in yellow when they finally fall.

golden rain tree
Photo courtesy of www.finkegardens.com

THE FRUIT: After the yellow blooms fall, they are followed by papery fruits that resemble little Chinese lanterns. They are a great conversation starter and kids love to pop them open to see what’s inside. Inside the Chinese lanterns are viable seeds that germinate if you look at them twice. The only drawback to growing golden rain tree is that it self seeds readily. In my opinion, the seedlings aren’t a real issue. They are easily removed even when they reach a foot or so tall. But perhaps, if you have a more natural area of your landscape that you don’t tend very often, golden rain tree may not be the plant for you.

golden rain tree
Photo courtesy of www.discoverlife.org

 

I want to be sure that you realize that there is also a plant called golden chain tree. It is not the same as the golden rain tree. Golden chain tree’s latin name is Laburnum x anagyroides and it is a plant that is better suited for areas that are cooler than Zone 7. Here in Virginia, it is a short lived tree that isn’t worth growing. When you go to the nursery to pick out your tree, make sure that you ask for a golden rain tree.

If you have a sunny or lightly shaded area in your garden that needs a small tree, consider the golden rain tree. It is disease resistant and not a choice for garden pests. If you keep an eye on the seedlings, I think that you will be pleased with growing a golden rain tree in your landscape. Do you have any experience with growing golden rain tree? If so, leave me a comment below or shoot me an e-mail. If you enjoy being part of the Mid-Atlantic Gardening community, join our e-mail list (upper right hand corner of this page), become a fan on Facebook and follow me at Twitter. Happy gardening!

 

Plant Profile: Kousa Dogwood (Cornus kousa)

Today’s Plant Profile is about one of my favorite small trees: the Kousa Dogwood (Cornus kousa). Kousas, as they’re commonly referred to, hail from eastern Asia and also go by the common name Japanese Dogwood. They are showstoppers in the landscape and for those who aren’t familar with them, expect the “what is that beautiful tree” questions to ensue.

kousa
Photo courtesy of www.rutgers.edu

 

As compared to the native dogwood Cornus florida, kousas bloom later in the spring. Here in Virginia, native dogwoods tend to bloom in April and kousas make their entrance into the flowering world in May. They also bloom when the leaves are on the trees whereas native dogwoods bloom before the leaves unfurl. Since the kousa blooms come out after the leaves emerge, they have a layered appearance that is stunning in the landscape. The blooms last for 4 weeks or more and carry the landscape into the early days of “unofficial” summer.

I enjoy using kousas in the landscape because they are much more tolerant of sun than the native dogwoods. So many times, well meaning folks plant native dogwoods in full sun and then wonder why it starts declining a few years later. “But it has more blooms in full sun” they say. Sure it does…and I hope that you enjoy them for the 10-15 years that the plant survives. If they are planted in the partial shade that they prefer in the wild, the trees will live a much longer life. But back to the kousa dogwoods. They are much better suited to full sun and actually prefer it over partial shade. Many new landscapes have little to no shade and kousas easily fit into these harsher environments.

Kousas rarely succumb to pests and diseases. Dogwood anthracnose has plagued our native dogwoods and I don’t personally recommend planting the straight species anymore. But the kousa dogwoods are there to fill the bill. There are many kousa cultivars that have hit the market recently. Let’s look at a few:

  • ‘Little Poncho’ – if you’re looking for a dwarf kousa that only reaches 8′-10′ tall in the landscape
  • ‘Milky Way’ – this cultivar is probably the one that you’ll see available most at garden centers. It has a broad bushy form and is loaded with flowers in the spring and fruits in the fall.
  • ‘Wolf Eye’ – this is a cultivar that has green leaves with a crisp, clear white margin. It is primarily grown for its foliage but it still has the same beautiful flowers as its non-variegated family members.

 

kousa
Photo courtesy of www.aragriculture.org

Kousa dogwoods have attractive salmon colored fruits that appear in the fall and are attractive in and of themselves.  The fruits can be eaten and turned into jelly or jam if your heart desires. That is if you can get to them before the birds and squirrels do…it’s pretty stiff competition in the fall.

Reaching 15′ to 20′ tall at maturity, kousas can be worked into virtually any landscape. If 15′ to 20′ is too tall for you, consider ‘Little Poncho’ for a smaller space. I hope that you will consider working a kousa dogwood somewhere into your landscape. Or if you have a kousa in your yard, tell other Mid-Atlantic Gardening readers your experience with them. Leave me a comment below or e-mail me at stacey@midatlanticgardening.com. Happy gardening!

 

Pests and Diseases: Glyphosate Damage to Trees

 

Today’s Pest and Disease post is a little different than some of the other topics that we’ve looked at such as gloomy scale or aphids. Today we are going to look at something that you may not even think of when you’re spraying weeds in your garden: glyphosate damage to trees. In case you’re not up on your chemical names, glyphosate is the active ingredient in products like Roundup and RazorPro. We have been told for years that glyphosate is biodegradable and has no residual impact on the soil that it touches. More and more, people are beginning to realize that may not be the case.

glyphosate damage to trees

Photo courtesy of Ohio State University

Dr. Hannah Mathers of Ohio State University has led the research on determining if glyphosate is responsible for cankers on trees where the chemical has been applied. The cankers resemble frost cracks that can occur during cold temperature extremes. The difference is that frost cracks generally appear on the south side of the tree whereas “glyphosate cankers” can occur on any side of the tree. The long and short of her research is that glyphosate is accumulating in the phloem of the trees and causing cankers and ultimately death. The death is a slow one as microorganisms move into the canker and set up shop. Glyphosate may not be the cause of death in the end but it is what allows the microorganisms a chance to kill the tree.

So how does the glyphosate end up in the phloem of the tree? It generally occurs one of two ways: the first way is by applying the herbicide around the base of the tree and having it come into contact with the trunk. You may not be trying to spray the trunk directly but if there are weeds at the base of the tree, you may inadvertently spray the trunk. The second way is through killing the weeds that grow within the root zone of the tree. That is, after all, probably why you are spraying herbicides to begin with. When these weeds die, they exude a small amount of the chemical into the soil which can then come into contact with the roots of the trees. The roots take up the small amount of glyphosate into the xylem of the tree but as it is transported throughout the tree, it ends up being stored in the phloem. Research indicates that the glyphosate can build up in the phloem for years and continue to cause problems for the tree for a long period of time.

Dr. Hannah Mathers has found that using glyphosate products that contain a surfactant exacerbates the problem. Surfactants are added to many pesticides to allow the chemical to “stick” to the target pest. The stickiness that results also allows the glyphosate to adhere to the trees if they are inadvertently sprayed. Unfortunately, virtually all of the homeowner versions of glyphosate contain surfactants.

So what can you do to avoid glyphosate damage to trees? MULCH! While I certainly don’t advocate the practice of mulch volcanoes, a 3″-4″ layer of mulch under your trees will keep most of your weed problems at bay. For the weeds that appear, hand weeding is going to be your best option. Also, consider planting perennials under the trees. A groundcover of plumbago (Ceratostigma plumbaginoides) will thrive in sun or shade and will form a dense mat that is almost impenetrable to weeds. If you don’t have to have the perfectly manicured garden, consider planting a nitrogen fixing plant under your trees so that the trees have a free source of nitrogen. Examples include members of the legume family such as peas and beans, alfalfa and clover.

I hope that you’ve gleaned a bit of useful information from today’s post. Take a look around your yard and other landscapes to see if you spot any of the “glyphosate cankers”. Let me know what you find by leaving me a comment below or sending me an e-mail at stacey@midatlanticgardening.com. Happy gardening!

March 13, 2012Permalink 2 Comments

Plant Profile: Paperbark Maple (Acer griseum)

 

In Monday’s Did You Know? post, I mentioned the Paperbark Maple (Acer griseum) and I promised that we’d look at it further in future posts. Well, today’s the day so let’s dive in. Paperbark Maple is a delightful small tree that reaches 20′-30′ tall by  15′-25′ wide at maturity. It is a slow grower so it will take many years to reach its ultimate size. In commercial settings, this plant would perform brilliantly in a courtyard where a more typical maple would overpower the space. In a residential setting, this tree can be used as a specimen or in front of evergreens to show off its beautiful bark. Paperbark Maple is often sold as a multi-stemmed tree but single leaders are available as well.

Acer griseum prefers moist, well-drained soil but will tolerate less. If it is planted in a particularly droughty area of the landscape, it will most certainly languish. This immediately rules it out for streetscape plantings where the trees are planted in those tiny little tree wells in the middle of a concrete jungle. Most gardeners enjoy tending their landscape so once it is established, it can fare quite well in most gardens. Acer griseum is native to China and is hardy in Zones 4-8. This fits the bill for all of the Mid-Atlantic gardening region.

Paperbark Maple is grown primarily for its beautiful, cinnamon colored exfoliating bark that is best noticed when the tree is bare in the winter. It is particularly breathtaking when viewed against a snowy backdrop. The bark peels off in curious thin, curly strips…in fact it’s hard to resist peeling the bark as you pass it by. Another noteworthy characteristic of this species is that it tends to cast dappled shade so ornamentals can be grown underneath…this is very different from the dense shade that a red maple or sugar maple cast.

The leaves of Acer griseum are a bit different from the typical red or sugar maple as well. The leaves consist of three lobes that sort of resemble poison ivy to me (remember the saying, leaves of 3, leave them be). Its leaves are plain jane during the summer but erupt into a magnificent array of colors in the fall. Paperbark Maple is often one of the last trees to change into its fall wardrobe, but the colors are magnificent…they can vary from yellow to orange, and red to pink. It’s interesting to note that the leaves can remain on the tree through the first part of winter in Virginia.

Paperbark Maple is not bothered by any serious pests or diseases so it can fit into almost any landscape. It’s especially at home in gardens where the caretaker is a bit more relaxed and likes for nature to take its course (that’s me by the way). If you have been looking for a tree that can fit into a small landscape and has year-round interest, Acer griseum should certainly be considered. I’d love to hear your opinions and experience with Paperbark Maple. Leave me a comment below or e-mail me at stacey@midatlanticgardening.com. Happy gardening!

Oh, just to give you a heads up, I am going to start delving into vegetable gardening in this Friday’s post. I actually have a reader question that deals with veggies so I may begin tomorrow (there’s decisiveness for you). I have to warn you: I LOVE, LOVE, LOVE vegetable gardening so this blog may tend to lean heavy in that direction for the next couple of weeks (or months). Send me your feedback and let me know if this is something that you are interested in…I’m here to help you with any gardening questions you have and I want to make sure that I’m meeting your needs. Thanks!

 

December 21, 2011Permalink 2 Comments

Did You Know? Tree Roots

 

I’m thinking of making the “Did You Know” posts a recurring theme for Mondays. Let me know what you think at stacey@midatlanticgardening.com or leave me a comment.

Did You Know that tree roots extend out much further than the drip line of the tree? It’s a common misconception that trees only have roots out that far but the truth is they have roots that go much further. It’s important to remember that as you consider construction and other home projects. You may not think that installing an asphalt or concrete driveway near your trees will cause them any harm, but think again. Also consider your trees before trenching (for fencing or irrigation systems) or tilling in an area that could compete with your trees. I’ve found a really great blog with awesome pictures detailing a root and how far it reaches out.

http://blog.thecareoftrees.com/bid/52821/Tree-Mythbusters

Check it out and let me know what you think at stacey@midatlanticgardening.com.

 

November 21, 2011Permalink Leave a comment