Top Performing Annuals

Last week I watched a “web” inar by Dr. Alan Armitage of the University of Georgia, Athens. For us plant geeks, Dr. Armitage is like a hero as a plant breeder and promoter of annuals and perennials alike. His webinar topic was “Best Performing Annuals,” and it covered both flowering and foliage annuals. At the trial gardens the plants are evaluated every two weeks for number of flowers, leaf color, disease and insect resistance and over all performance. The data are then combined to come up with a single performance score.


It is important to us as retailers to only sell plants that we know perform well. It is also important to everyone up the marketing and production chain. So seed companies, growers and retailers all have an interest in making sure the plants we grow and sell will perform for the end user, you our valued customer. There are all kinds of trials that are done to make sure we all get it right. The most famous is probably the California Pack Trials, but other organizations also host these types of trials, including our land grant universities. When I was a grad student at Michigan State University, the entire campus was an All American garden and it was a big deal during the summer when the seed company execs would come to see how their plants had performed well and which would be going on to full production.

Well Dr. Armitage offered up some really cool plants and here are just a few that caught my eye. As you look through your gardening magazines and start to plant for your containers for next summer keep these in mind. Also here is the link to Dr. Armitage’s web site. You can see pictures from their trial gardens and learn about how you can visit if you are ever down that way.

Breathless Blush– This is a euphorbia similar to Diamond Frost but with a pink blush to the flower. It makes a great “filler” plant in a container and would go well with silver toned foliage plants and darker purple petunias.

Sun Patiens– These impatiens are bred to be more sun tolerant than regular impatiens, tho even those will do well in sun if given enough water. The cool thing about some of the sun patiens (I think) is the foliage. Several varieties have variegated foliage, which is quite stunning.

Zinnia– Zinnias are some of my favorite annuals. Their flowers are very colorful and last a long time on the stem. They are a traditional flower for the cutting garden. That said they are somewhat spindly and need to be planted at the back of the garden. The Zahara series was profiled on the webinar and were very nice. Another more compact zinnia is the Profusion which comes in a variety of flower colors.

Celosia– Michael is not a fan of celosia because it is prone to mildew with the type of flower that is has. The “plumed” varieties retain a lot of water and fall over due to the weight in the flower head. I think the “cocks comb” variety is very unique and would look good toward the front of the container.

Ornamental Peppers– We most often think of these as accent plants for our fall containers, but when I was at MSU all the summer annual beds were edged with ornamental peppers. It was truly beautiful.

Pennisetum Jade Princess– This is a relative of the purple fountain grass that is so popular in containers but has that brilliant jade coloring. Like the purple fountain grass it is not hardy in our climate so don’t expect it to come back the next spring. Like its purple cousin the seed head will attract birds in the fall.

I hope this has given you some ideas for next spring when planning your containers and gardens.  I know after this last week and our frigid temps it probably seems like light years away but it will be here sooner than you think.  Remember we are always available at Countryside to help with any of your gardening questions.  If you are interested in seeing what a trial garden looks like, the closest one to us is the Ball Seed Garden in West Chicago.  They have a big "Open Day" in August when visitors are welcome to visit and Master Gardeners are on hand to answer questions.

More Fall Chores

Thanksgiving is a good marker for many garden chores.  It is still too early for any pruning, especially for roses, which have not yet gone dormant.  You may also want to clean up your perennial beds.  I personally like to wait until spring.  The stems and dried seed heads can be quite attractive covered in snow.  There is a benefit to leaving the stems on as it does protect the root crown.  If you feel you must cut them down now, leave at least 6" of stem above the ground.

But here is something to do if you have broadleaf evergreens, such as boxwood, azaleas and rhododendrons.  The rain we had last week didn't amount to much at my house and it has been so dry up to this point, it is a good idea to give these plants and your evergreens a long drink of water, especially the azaleas and rhodies, as they are very shallow rooted.  Another good practice is to spray them with an anti-transpirant.  This is a waxy coating that keeps them from drying out.  Wilt-Pruf is one brand, Wilt-Stop from Bonide is another.  These pictures from Wilt Pruf show the difference when

one is treated and one is not.  The waxy coating prevents the plant from drying out when the ground is frozen and the plant cannot take up water.

Wilt Pruf and Wilt Stop can also be used on holiday greens used in decorating.  If you decorate your patio containers for the holidays give them a spray of the Wilt Pruf or Wilt Stop.  This will usually keep them looking good through late winter. 

Preparing Roses for Winter

Roses can be tricky to grow here in Northern Illinois. Selecting the proper type of rose is one way to ensure success in growing roses. Proper care is essential.

I have grown hybrid tea roses in the past but not very successfully. I’d always lose one or two over the winter. I did notice that the shrub roses I had required little care and always came back the next spring. Shrub roses are much hardier than hybrid teas and though you do sacrifice bloom size you make up for it in sheer quantity of blooms. Most climbing roses perform similarly. I have a chain link fence on one side of my garden and a couple years ago decided to plant a climbing rose to help hide the fence. I chose a zephirine drouhin, which is from a very old class of roses and very fragrant. It only blooms once a season but it also tolerates some shade.

Proper pruning in preparation for winter is key to rose growing success. Pruning any plant encourages new growth. This new growth will be very weak and will not survive over the winter. It will add stress to the plant and could end up killing the entire plant. It is important to wait until the rose is fully dormant before doing any pruning, such as you might do to fit a rose cone over it.
Yesterday I was planting some bulbs around my climber and I was stunned to see how much new growth has occurred this fall. There are new lateral branches emerging from the main canes as well as 6-8 inches of new growth at the end of the main canes. This rose is now where near dormant.

Winter Pruning Tip: Wait until all the leaves have fallen from the rose before pruning. If you use rose cones don’t put them on until the plant is fully dormant and can be safely pruned to fit under the cone. Some years this may not occur until late December! Alternatively, you can use rose collars. These are tall strips of plastic that wrap around the base of the plant and allow you to backfill with top soil or garden soil to protect the rose. Also, remember, the purpose of winter protection is not to keep the rose from freezing but rather to keep the rose in a chilled state and avoid the temperature fluctuations from mid-winter warm ups.

If you have shrub roses, you really don’t have to do much to prepare them for winter. You’ll never get them to fit under a cone or get a rose collar around them. They really don’t need the protection anyway. Next spring just prune out any dead canes or branches and give it a good shaping.

Most climbing roses bloom on old wood from last year’s growth so you don’t want to prune in the fall. You can selectively prune out dead canes in the spring or if you have to cut them back do it right after they have bloomed

If you have questions about what kind of rose you have, check with the Countryside greenhouse staff.

Fall Lawn Care

I spent most of the day raking leaves. What a chore-- and a waste. Leaf compost is such a great addition to the garden soil. Really, adding any type of organic matter can improve just about any soil. Soil too sandy? Add organic matter. Soil to heavy? Add organic matter. Soils to alkaline? Again, add organic matter. Alot of people like to use mushroom compost, which contrary to its name, is not made from mushrooms but rather the compost (the straw from horse manure, poultry litter, ground corn cobs, rice hulls, etc) in which it is grown. It can be high is salts and is not the best compost to use in our heavy clay soils. Since we have so many leaves this time of year, why not compost them instead of burning them or adding them to land fills?

My neighbor down the street piles all of his leaves directly on his veg. garden and then tills them in right before he plants in the spring. If you don't have too many leaves to deal with you can just run them over with the mower and shred them. Don't leave too thick a layer (you may want to mow several times or rake them out) since they will smother the grass which leads to many more problems next spring. Also make sure you rake the leaves out of the flower beds because a thick layer of leaves will also smother your perennials. You could rake back in shredded leaves because they break down much more easily than non-shredded leaves.

I have a rotating composter so I am going to shred the leaves with the mower and then add them to the composter. I am hoping to get a good ratio of brown (leaves) and green (grass clippings that are high in nitrogen and gets the whole process started). I am also going to make a more concerted effort to add appropriate items from the kitchen to the composter. I did this last year and got a nice batch of compost but then sort of lost interest. My brother just digs a shallow hole off to the side of his yard and fills it in with the leaves and a few shovels full of dirt to start the composting process.

As we go into the winter season, you might want to consider giving the lawn one last feeding with a low nitrogen fertilizer (10-1-10 is a good analysis) but one that is high in insoluble nitrogen so that whatever the grass doesn't absorb this fall will still be in soil for the grass next spring.

Also begin to lower the deck on your mower. Usually we recommend a mowing height of 2-3 inches but as you get close to your last mowings gradually lower it to 1-1.5 inches. This will help prevent winter diseases like snow mold.

The Big Freeze

We are supposed to get a hard frost tonight so for all intents and purposes our growing season is over. Last weekend I brought in my tropical patio plants after a touch of cold got my taro. It is recovering but several of the leaves are toast. At the last minute today I decided to try to over winte my rosemary plant. I like cooking with fresh herbs and it was great having an herb container right outside my kitchen door. The basil had gone to flower months ago, but the thyme and rosemary were doing well. Thyme is a perennial, even here, but not the rosemary. Since it was going to die anyway I figure I don't have anything to lose by bringing it indoors.

There are a few things to remember about bringing plants indoors. More than likely I will have brought in a few unwanted guests (insects) with my plants. I can use systemics on my tropicals but not on edible plants. I can get sticky traps and wipe down the plants to try and physically remove any insect eggs from the leaves.

Usually the plant will undergo a kind of "culture" shock when brought indoors. Even the sunniest spot in your house is not the same as being outside in the sun. You may notice the leaves drooping or even dropping. Resist the urge to water unless you have checked the soil and found it dry. Dropping leaves is a natural part of the plant's effort to acclimate itself to its new environment. Eventually (hopefully) the leaves will grow back and these new leaves will be acclimated to the new conditions. Also, resist the urge to fertilize. Feeding a plant when it is not growing much causes the new growth to be weak and leggy.

I have a spot behind my kitchen sink that is pretty sunny and also conveniently located for cooking so that is where my rosemary will go. I hope it likes it there.

Another factor in surviving winter months for all house plants is humidity. When the furnace is running it really dries out the air and this is bad for most plants. Most plants like about a 50% humidity level. You can increase the humidity around the plant by misting it periodically or by placing trays of water near the plant. Lori always recommends filling a saucer with pebbles and then adding water. Put the plant on top of the pebbles so that it is not actually sitting in the water. This will create a constant humidity dome around the plant.

Over Wintering Tropical Plants

Saturday morning I stepped out on my back deck to discover the temperature had dropped so low overnight that my taro plant (colocasia) leaves were all curled. I drug it in the house and no permanent damage seems to have been done. So we all probably need to think about bringing in our tropical plants and digging up the non-hardy bulbs in the garden. Some plants do seem better able to handle the stress of being indoors than others. My hibiscus and jasmine do just fine, but the Princess Flower I tried to overwinter last year made it to about February then just died. I haven't had much luck with gardenias either. So I guess what I am saying is that as beautiful as some plants are it's just not worth the effort. Pitch them onto the compost pile with no regrets.

Another thing to be mindful of when bringing plants indoors, is what else you may be bringing in. Insects often lay their eggs on the undersides of leaves or in the soil and when you bring plants into a warm room the eggs will hatch and now you have an insect problem. There are many products on the market suitable for houseplants. Ann Larson from the Countryside greenhouse recommends cleaning the plant leaves with an all-purpose cleaning product we sell. You can also use systemic insecticides or sticky traps.

For my hibiscus and jasmine, I just drag them into my dining room, where they apparently get the right amount of sun because they do just fine. The hibiscus has even bloomed in there in January-- what a treat that is!

The canna are also easy to overwinter. I just let them die back in their containers and put them, container and all, into the the basement where it is cool and dry. Last year I did the same with the taro.

Other plants to overwinter:

Gladiolas-- When the foliage has died back, use a garden fork to lift them from the ground. Let them dry and clean the dirt off. Place them in a box with some peat moss or shavings and put them in a cool dark place. When the soil has warmed up in the spring you can plant them again. When you are digging you will find tiny bulblets--baby glads, if you will. Store them as well and replant in the spring. It will take a few years before they are big enough to bloom, but they will eventually.

Dahlias-- This is another garden favorite known for its large colorful blooms. These are actually tubers, and they can be over wintered as well. After the first frost, use a garden fork to lift the tubers. They can be quite large so be prepared. Let them dry for a day, and then cut off the stems, clean off the dirt and store in a box with peat moss or shavings in a cool dark place.

One of the benefits of overwinter bulbs and tubers is that you are saving older more productive tubers and the result the following year should be bigger blooms.

Travel in Guatemala

Mike in the greenhouse has a saying, “Everything is a perennial somewhere.” (The corollary is “Perennial does not mean eternal,” but that is a topic for another day.) This was really brought home to me last month when I spent a week in Guatemala with my dad and the Bend, OR area Habitat for Humanity group building houses.

Guatemala shares its northern border with Mexico and its southern border with El Salvador. In the 90s many US companies had textile plants in several Central American countries sewing garments. These business have now moved elsewhere in the search for cheaper labor and their economies have really suffered. Our build site was in the western highlands town of Quetzaltenango, which means “place of the quetzal,” their national bird and name of their currency. Their were about 15 people in our group. My dad, Fred, was the oldest participant at 78 and the youngest was 16. It was a great group of people and we were able to shave about a week off the normal time it would take to finish these very basic concrete block houses.

But, back to the plants...
One of my favorite tropical plants is Tibouchina urvilleana or Princess Flower. It has masses of purple flowers and velvety leaves. It is zoned 10-11 so it does not winter over here in Crystal Lake, IL. Mike and I have both tried to over winter it indoors. It makes it to January or February and then croaks. Naturally they thrive in Guatemala where I saw it planted in many town parks and plazas and about 5' tall.

Impatiens (shade) and pentas (sunny and attracts butterflies and hummingbirds) are used as annual bedding plants here. There they can winter over from one season to the next and get the size of small shrubs. I saw a New Guinea Impatiens with stems the size of your thumb. I will say there is a tradeoff. None of these were blooming in years 2 and more the way they do in year 1. I don’t know if this was because they weren’t getting fertilized or if they were just “fatigued” and needed a good pruning.

Another plant I saw reach its full potential was croton. Ann Larson sells these in the interior plantscape department. They have large yellow/bronze foliage and make a great house or office plant. I have seen them used in the borders at the Boston Public Garden to great effect. In Guatemala they were as big as small trees. Unbelievable.

Finally, because I know Lori will be thrilled to know that someone loves irisine, I saw it everywhere– in the median strip of large boulevards, at highway interchanges, everywhere where no one wanted to spend a lot of time on maintenance proving another favorite saying “Every plant has its place.”