Perennials

The most commonly misunderstood collection of plants are perennials. The name perennial suggests that they should appear each and every year for the remainder of time but this is not necessarily so. There are several factors that affect the survival of perennials that are important to know in making choices for your garden.

One of the first “perennials” I had contact with growing up was “Hosta funkia”. My parents added an extension to their driveway along the side of the garage so the garden in this area had to go. My father saved some of the perennials and replanted them at the end of the asphalt. Every year, they showed up with their purple flowers and even though it was years later that I learned their name, I have never forgotten their loyalty.

Hosta belongs to a group of perennials called “herbaceous” perennials. They are NOT necessarily herbs. They are called herbaceous because the above ground part is not woody and most die back to the ground each fall and sprouts out from these roots each spring. Herbaceous perennials are my MOST favorite because their roots can be dug up and divided with a shovel and spread around the yard in all of the gardens, for free.

When growing perennials there are some cultural basics to remember:

1. It is important to remember what the leaves look like. Take their picture and place markers so they don't inadvertently get weeded in the spring. This is one way the whole perennial thing goes down the drain.
   
2. Allow the flowers to remain in place and reseed themselves. Sometimes the winter temperatures are harsh enough to kill the roots and the seeds insure the perennial lives on.
   
3. Leave the tops in place over the winter. Commonly, perennial gardens are cleaned up with the leaves in the fall and the tops are removed to make the garden look neat but this really works against the plant. Some plants are semi-evergreen and continue surviving through the winter.
   
4. Keep leaf blowers away from a perennial garden. Leaf blowers also blow all of the seeds out of the garden too. Some perennial plants are really “biennial” and need the seeds to secure future generations. A biennial has two growing seasons. The first season the vegetative portion, with no flowers, will grow. The second growing season of that same plant will produce a flower. That flower will go to seed and supply the third growing season with the vegetative portion. A good example of a biennial is Lunaria annua (Money Plant, Honesty Seed).
   
   

There are lists of herbaceous perennials on the internet but the key to selecting ones for your garden is finding the ones that mirror your gardening philosophy. Some people like to be involved while others want to plant it once and forget it. Both are acceptable, so be honest about the level of participation that is acceptable and the garden will end up bringing pleasure and not pain. Improvements have been made to some of the labeling of perennials but it is helpful to research plants of interest. Focus the research on:

1. Winter hardiness. Check the specific variety of the plants for their winter hardiness in your planting zone. This is especially helpful when ordering via catalog and is just good plant selection criteria.
   
2. Propagation. Propagation is a method of plant reproduction that can be sexual (seeds) and asexual (division, cuttings, grafting). Propagation describes methods of reproducing the parent plant which can be through seeds but in the world of plants can also be by digging up and dividing the roots, bulbs, corms, tubers, and rhizomes. It can also includes reproduction by cuttings and grafts.
   
3. Biennial – some perennials are called both biennial and perennial which is correct but is a clue to do more research. The Lunaria annua, mentioned earlier, is an easy biennial to work with. The vegetative plant is not very interesting but the second year plant produces purple flowers on a stalk in the early spring and as the season progresses the base of the flower, called the ovary, swells and products round flat pods about the size of a quarter, which gives it the common name, Money Plant. In the fall the outer covering on the pod dries and separates and the seeds are exposed. The process can be moved along by hand and the seeds harvested. The portion of the plant remaining is a translucent skin that is quite lovely and becomes a great dried flower arrangement. After the seeds are harvested, that is it for the parent plant, so failure to harvest the seeds may result in the plant petering out.
   
4. Native – While there is a movement to plant native species, it is prudent to make sure they are not on the invasive species list in your State. Invasive species are plants that over compete and in the process win over the preferred plants. The Common Daylily, Hemerocallis fulva, is one of those species to avoid. While it looks pretty when it is flowering it is a strong competitor that will crowd out and usually win over other perennials in your garden. It is considered native in Maryland but should not be encouraged. There are many other varieties of Daylilies to pick from that are a lot less competitive and are very consistent at coming back year to year. Their roots are tubers that can be divided at the end of every growing season to share around the yard.
   
5. Light – When the tag says FULL SUN it means the plant needs at least 8 hours or more. If the tag says part shade the plant needs 6 to 8 hours. That means that if they are next to a house or near a tree the duration of the shade cast by the structure or the tree has to be subtracted from those hours. Otherwise they will just fade away. Light really matters.
   
6. Soil type – Most ID tags do not specify a soil type. Most perennials will survive in most of them anyway but if you have an extreme like sandy, swampy, or a new construction site where the soil could be compacted or bereft of organic material, like the subsoil left after construction, pay attention. The soil will need amendment, or select plants that will survive in that specific soil type.
   
7. Insect larvae – ID tags also do not specify what type of insects affect different perennials. There are, however some insect larvae who's population levels can rise and fall with the seasonal weather patterns. I have noticed Japanese Beetle larvae while planting and after losing a perennial, I dug up the remains and found larvae curled around the roots. There are times that further investigation is warranted to see if you can find a secondary source of the plants distress. Keep or take a picture of the culprit and take it with you to the garden center to find out what can be done to save the remainder.
   
8. Forage – probably the most challenging reason attributed to the disappearance of perennials has to do with the wildlife living around and among these plants. I have had entire gardens stripped in the time it took to take a shower after working in the garden all day. I had no idea those rabbits lived there. Over the years there have been herds of deer, chipmunks, squirrels, mice and our constant family of rabbits to test those perennials left in our garden. We have also resorted to the use of flowering shrubs to give the plants some substance so there might be something left at the end of their foraging. My favorite control has been the use of particularly perfumey smelling soap. There are lists on the internet when searching for plants that wildlife do not like to eat. But in the fall when food stores are becoming more scarce even those plants are fair game. Try fencing, netting or your own brand of smelly soap and see what survives.