In The Garden

In the Garden

Ralph Purkhiser, Purdue University Master Gardener

     The rains during the past week have brought down most of the leaves, and the remaining leaves will likely be falling soon.  These November rains are a blessing.   While drought conditions plagued southern Indiana for most of October, November has brought some much-needed moisture.  This is important, since plants need to have adequate moisture to prepare for the coming winter.  Even though the tops of trees, shrubs and perennials may seem to be sleeping, there is still active growth in the root system, and this will continue until the ground freezes.  This is especially true of recently-planted plants.  The moisture is needed to allow them to produce a good root system, which will anchor them through the winter.  One of the greatest challenges for plants in an Indiana winter is heaving, caused by the freeze-thaw cycles that typically occur.  This heaving will actually cause the root system to be lifted out of the ground.  If the root system is not extensive, the whole root ball may be lifted, and if this is not corrected, the plant may be killed during the next freeze.  That is the reason one should wait until a freeze, and then apply a layer of organic mulch, to insulate the ground and keep it frozen.  That will prevent heaving.

     This heaving is also one of the reasons that gardeners should inspect their gardens regularly in the winter, especially any time there is no snow cover.  If one finds plants that have been heaved out of the soil, they need to be pressed back down in the soil.  Mark them and apply mulch during the next freeze.

     Those fallen leaves are a source of much controversy in the gardening and naturalist world.  To be truly natural, the leaves should be left to decay in place, enriching the soil and providing organic material.  However, heavy leaf cover may smother grass and other plants.  The leaves also provide shelter for many insects.

     You have many options for leaves, and I leave it to each person to choose what works best in his or her situation.  I use different methods in the various parts of my garden.  In the wilder areas near the woods, I usually just leave the leaves.  However, wet leaves can become a problem in areas where I will be walking during the winter.  I choose to use a leaf-vac to clean walkways and the leaves that blow onto decks and porches.  This device shreds the leaves as it picks them up, and that will likely kill the insects in them.  Still, these shredded leaves are put to good use.  I will apply them to my raised garden beds, where they will decompose over the winter and add organic material to the beds.  In the grassy areas of the garden, I usually pass over the leaves with the lawn mower.  This shreds the leaves and the resulting leaf cover is usually not heavy enough to kill the lawn.  In other areas, I rake the leaves into the many perennial beds, using them as mulch.  I also have to remove leaves from the drainage ditch along the county road.  These leaves are often wet and matted together.  I make a pile for them in an area at the edge of the woods.  By spring, they will have become a wonderful leaf mold that I can use as mulch in the gardens.  There are two common leaf-removal options that I do not recommend.  In some areas, it may be necessary to bag leaves, but I find that to be a great waste of organic matter.  Most landfills no longer allow bagged leaves and yard waste.  Some municipalities require that leaves be bagged in paper bags that will break down and add to the organic material.  The worst leaf-disposal option is burning.  This will kill all sorts of insects and add to air pollution.  It also is a terrible waste of good organic material that will feed the soil.

     If there are children who play in your yard, please rake at least one big pile of leaves and let them jump in them.  Every child needs to experience the joy of leaf diving.

In the Garden

Ralph Purkhiser, Purdue University Master Gardener

      This past week, beautiful weather made for near-perfect gardening conditions.  At Sandhill Gardens, we received enough rain to soften the soils, giving good conditions for planting shrubs and perennials that I bought at the fall clearance sales.  However, I admit that a lot of the time I spent in the garden this week was just enjoying the beautiful weather and marveling at the flowers still blooming as the calendar turns to November.  The foliage in the garden and in the woods over the cliff has also been spectacular.  This is a bit of a surprise, as I was bracing for a season without great fall color, due to the drought conditions.  Leaves have been falling, but some pretty foliage remains.  Still, there have been some disappointments in my garden walks.  I have had some young trees attacked by deer, including two of my pagoda dogwood trees.  I am just hoping they will grow back from the roots.

     There is a lot of controversy concerning cleaning up the garden in the fall.  On one hand, insect pests and fungal diseases may over-winter in the spent plant material.  On the other hand, that same dead plant material provides protection for beneficial insects, including pollinators.  Seed heads also provide food for birds and other animals.  What’s a gardener to do?

     I would not presume to answer that for you.  You have to decide what works best for you and your garden.  My personal solution is a mixture of clearing and leaving old growth.  I clear almost everything in the vegetable garden and plant some type of cover crop in the raised beds.  If there has been any disease, I put the plant material in the burn pile and wait until we have some wet weather to safely burn it.  Otherwise, I shred the material and put it in the composter.  Since I like to decorate the garden for Christmas, I try to clear out most of the dead material from the garden areas near the house.  I will cut off seed heads and put them either in the meadow or in an area at the edge of the woods.  The stems will go to an area near the woods.  In the spring, after temperatures climb back into the fifties, I will run them through a shredder and use the debris for mulch.

     Elsewhere, I will leave perennials and grasses standing.  The meadow will provide food and shelter for many creatures through the winter months.  The ornamental grasses will also provide winter interest.  The seed heads sparkle when there is frost on them and the sun hits them in the morning.  The larger clumps also look nice with snow on them, and the movement of the stalks in the wind provides visual interest and also the sound of rustling grass.  All of these will be cut in the spring when the clumps begin to grow again.

     Bulb planting continues at Sandhill Gardens.  I had to buy a new cordless drill to use the bulb auger.  That gadget makes bulb planting much easier.  I was given several bulbs this week and also found some on clearance sales.  There is still plenty of time for planting bulbs in southern Indiana.  I have planted on January 1 and got flowers that next spring.  Watch for sales on bulbs.  As long as they are firm, they should grow.  You will reap the rewards next spring.

In the Garden

Ralph Purkhiser, Purdue University Master Gardener

     Last week, we discussed topping, coppicing and pollarding trees.  This week, we will continue with what are considered finer types of tree and shrub trimming.  These trimming techniques are actually art forms.

     Topiary is the art of trimming plants into controlled shapes.  This may range from geometrical shapes to making a plant resemble an animal, a machine or even a person.  Topiary also includes growing vines and herbaceous plants on wire forms to create a particular shape.  Topiaries are often found in very formal gardens, and also are used in amusement parks and many educational institutions. 

     Some plants lend themselves to topiary.  In general, a good topiary candidate is a plant with small leaves and is capable of producing adventitious leaves on old wood.  Topiaries need frequent attention.  As plants grow, the new leaves may disrupt the intended shape.  At the Palace of Versailles, gardeners use scissors to trim back errant growth on a daily basis.  I once visited the magnificent topiary gardens of Mr. Pearl Fryor in Bishopville, South Carolina, and was amazed at the fanciful shapes this self-taught artist had shaped from trees and shrubs.  However, I later learned that Mr. Fryor had developed health problems, and the gardens quickly deteriorated.  Luckily, a local group formed to get the garden back in shape and the volunteers continue to maintain the garden.  Many people have been charmed by the spirals carved from spruces and yews, only to discover that maintaining those forms requires frequent and skilled trimming.

     Another decorative trimming style often found in formal gardens is espalier.  This is the practice of trimming woody plants to grow nearly flat against a wall or a fence.  Espaliered fruit trees allow fruit to be grown in gardens that might not have the space for a traditional orchard.  Like topiary, espalier requires frequent attention.  Wires or twine are often used to train branches to grow in particular directions.  A popular espalier shape resembles a candelabra.  The making of an espalier garden requires years of training and practice.

     One of the most popular trimming styles is the art of bonsai.  The word simply means “trees in trays” in Japanese, but over centuries in the orient, the art form has evolved into a precise cultivation method.  I have often heard people refer to a bonsai tree as if it were a particular species.  Actually, almost any tree may become a bonsai specimen.  In addition to trimming and shaping the above-ground portion of the tree, bonsai requires pruning the roots.  The traditional goal is to create a miniature form of a tree that is gnarled and windswept, such as one finds in the mountains or other harsh environments.  As with espalier, trees are often shaped by wiring the limbs to train them to grow in a desired shape.  Experts also carve hollows in trees.  Leaves are often removed until the tree develops smaller leaves.  Special growing media are usually used for bonsai specimens, often lacking organic components that hold water.  Therefore, bonsai trees require frequent watering and attention.

     These short descriptions of specialized trimming arts are not intended to be comprehensive.  If you are interested in any of these methods, I urge you to get involved with a master of the art you choose.  I certainly am not an expert on any of these methods, although I like to dabble in them, and I certainly appreciate the work of the masters.

     Fall colors are at their peak in southern Indiana.  Get out and enjoy the beauty of nature.  If you do not have a favorite viewing place, come sit with me in the giant hands at the top of the cliff at Sandhill Gardens.  The colors in the valley below are especially magnificent at sunset.

• Lifestyle

In the Garden

Ralph Purkhiser, Purdue University Master Gardener

     In a recent column, I mentioned a pollarded tree in my landscape, but did not give a lengthy explanation about pollarding.  That has generated several questions this week, so I thought I would write about some of the trimming methods used in the landscape trade.

     Tree topping has long been a method used to control the height of trees.  Utility companies used to top trees along their rights-of-way (That is the correct plural.)  Men working from bucket trucks would cut off the upper branches of trees to make them shorter than the adjacent utility lines.  Sometimes, people would also hire tree trimmers to top other trees in their lawns, often fearful of large trees towering over their homes and other buildings.  The problem is that topping usually creates more problems than it solves.

     Indiscriminately cutting the branches to a particular height means that many, if not most, of the cuts will not be at branch junctions.  That means there will be many stick-ups left in the tree canopy.  When a tree is properly trimmed at the collar near a branch junction, the tree is able to heal itself.  Stick-ups do not heal quickly, inviting insect damage and disease to enter the tree.  New growth also becomes a problem.  Junction cuts, since they scab over quickly, do not usually result in new growth.  Stick-ups will sprout new growth, which is usually straight up and spindly.  Within a few years, that growth will reach the utility lines and the whole process must be repeated.  The new growth is also usually weak, so the branches often break in the wind and fall.  When people top trees near their homes because of fear of falling branches, they actually increase the likelihood of falling branches from the re-growth. 

     There are good reasons for removing part of a tree’s canopy, but it should be done by an arborist who knows to cut branches only at branch junction cuffs.  Removing dead or damaged branches or branches that are rubbing against a structure will improve a tree’s appearance and make it safer, it the trimming is properly done.

     Coppicing and pollarding are really forms of tree topping, but are done for specific reasons.  In medieval times, before crops like corn and soybeans were introduced to Europe, farmers often depended on trees to provide silage to feed animals through the winter.  Wood was also a common heating fuel and was used for construction.  Many utensils used in everyday life were often carved from wood.  Soon, the demand for wood products was greater than natural forest growth could supply.  They noticed that some trees would re-grow from the stumps left after cutting a tree.  That re-growth was usually straight, making it good for posts and building materials for boat construction.  Harvesting during the summer also allowed farmers to make silage from the leaves of the re-growth, and thus the practicing of coppicing was born.  Land owners would harvest an area of coppiced trees on a regular rotation, usually every two to six years for animal feed or every eight to ten years for wood, depending on the species and the planned use of the wood.

     Coppicing had some drawbacks.  If one pastured animals in the woodland, they would eat the leaves before they could be harvested.  That gave rise to the practice of pollarding.  In pollarding, the original trees would not be but to near the ground.  Instead, stubs would be left tall enough to keep the animals from grazing the canopy.  Wood lots managed by regular harvesting may supply livestock food and wood for many years, but the trees must have regular attention.

     Eventually, someone decided to coppice and pollard trees to produce a particular look in the landscape.  Many European grand estates have lanes lined by pollarded plane trees, looking like rows of lollipops along the lane.  Maintaining such a look requires a lot of work. 

     Next week, we will explore some other trimming techniques used to produce ornamental trees.