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Back more years than I can believe, when I had many acres of fruit trees, mid December was the time to assemble chainsaws, limb loppers and ladders and begin a pruning assault that often lasted into late April or early May.

To end my ramblings for the 2007 gardening season I will offer a brief calendar that you can hang with your pruning tools if you wish. Using the first paragraph as a lead I will start with fruit trees.

Apples, pears, grapes, sour cherries and blueberries should be dormant pruned. I started with the apples in December and tried to finish the grapes in March. If you have just a few of these I would attack in late February or early March.

Peaches, nectarines, sweet cherries and plums are much more bud tender and early pruning increases the risk of crop failure due to winter bud damage. Jokingly and seriously, the often offered rule of thumb is to work so that half of them are pruned before they bloom and half are done after bloom.

Christmas tree growers will tackle their short-needled evergreens in late winter hoping to be done before too much sap flows. That rule applies to all conifers except pines, which can be quickly identified by their long needles. Most, if not all, of the short needle conifers will tolerate severe pruning and will rejuvenate from even a vicious attack.

Pines are much more sensitive. Only the new growth as it matures in late May or June should be cut. Cutting pines into old wood, last years or older, seldom yields any rejuvenation.

Deciduous trees should be dormant pruned. If you are alive you can't help notice that the utility company's pruning crews are in full action. Many of you would deny that what they do is pruning, but in reality their message is; put appropriate sized trees and shrubs under the utility lines.

Flowering shrubs quickly fall into two categories. They either bloom in the spring or they bloom in the summer and fall.

If they bloom in the spring, they set buds the previous summer. Dormant pruning of spring bloomers will only remove flower buds. They should be pruned as the flowers fade, leaving time for regrowth and the formation of flowering buds for the next season.

Fall bloomers work off of new growth and are often a bit more winter tender than our spring bloomers. Prune them after you see the extent of winter twig damage. I think April into May are good dates to remember.

That's the calendar, so I'll close with a few more things I think about when I prune.

I try to do the job with as few cuts as possible. In other words, prune with your eyes and then get the loppers. Always remember, it is unwise to start with a plant that is too big for the spot and then fight to keep it under control.

Also, I have learned that if a plant is growing too fast, pruning in July or very early August can be a great taming tool. I regularly used that technique in the orchard. Less fertilizer and water will also slow the wild ones down.

Grudgingly, we can no longer deny that winter is near. My life is built around the flow of the seasons. For me it is time to rest, enjoy the season and plan for the spring. Hopefully, you can find time to do the same.

The Monday before Thanksgiving I ventured a bit north of here and was startled by the white roofs and the patchwork of snow and green on the ground. I guess that season is nearing.

On the way home I could still get excited about the colorful leaves clinging desperately to a significant number of trees. The wind, rain and temperatures of the last week have done the job on most of the leaves near my house.

That leaves one important garden chore perhaps undone. Yard grass and a heavy coat of leaves are not friends. Rake them, blow them or visit them with several passes of the riding mower, but whatever you do compost them or incorporate them somewhere in the garden.

Maple leaves, especially the large ones found on the common Norway maple that was a favorite planting 20 or 30 years ago, will kill most grass if left where they land.

Another job that could be waiting is the mulching of any plants you added this fall. Waiting for temperatures that freeze the soil and then mulching will prevent or minimize heaving caused by the ups and downs of temperatures that we have in the winter.

I did a lot of early fall mulching, only to read that mulching too early is a winter lodging invitation to moles and voles. I have spotted a few mole tunnels, but probably not enough to be concerned.

Moles are those stubby fat ones with the pointed noise and tails who are seldom seen above ground. They eat grubs (insect larvae) and will not generally damage plants except in very high concentrations. Their tunnels just contribute 'ugly' to the landscape.

Voles, on the other hand, are small, skinny, hopping mice that will do a number on tender bark and roots. The problem is that they love to share the mole tunnels.

As a kid I remember dad had a serious collection of slabs of tin and plywood he used in the orchard. A slab, some poison and a big stone or cement block was his answer to voles that can devastate fruit trees. My working cats are also quite effective.

Returning to the thought of snow and, of course, clearing it comes to mind. The first defense is a shovel, snow blower or some plowing device. What I want to comment on is what then.

Most of us use some salt or snow melt to keep our walks clear of ice. They work chemically by lowering the freezing point of water melting. Their chemical action continues in the nearby soil or runoff areas.

Usually this is not an issue, but if you use a lot of these materials, have plant problems along your walk or drive, or have some landscaping beside a public road it might be wise to consider some salt tolerant plants.

Other options include sand, gravel or mulch. They melt snow when the sun warms their dark surfaces. They work about as well as the chemicals. For me, sand refills the cobblestone walk while mulch can easily be sweep into the adjoining flowerbed.

If I wasn't a fan of our changing seasons I wouldn't like winter. On second thought, tolerate might be a better word.

Last week I told you about who plant breeders are. This week, we'll talk about what they do.

Breeders travel around the world for undiscovered specimens to cross with existing plants. The Wave petunias were bred by a Japanese beer maker searching for new hops in South America. He brought one of the wild petunias back to Japan and crossed it with garden petunias and Voila! A petunia that revolutionized your flower bed.

Sometimes, they stay at home. Jim Ault at the Chicago Botanic Garden and Richard Saul at Itsaul Gardens in Georgia crossed 2-3 native North American coneflowers to get the new yellow, orange, and reddish-pink echinaceas that are so popular for late summer perennial borders. The Meadowbrite series came out of Chicago and the Big Sky series came from Saul's efforts in Georgia.

The mechanisms of plant breeding are simply taking pollen (male) from one parent and putting it on a receptive flower stigma (female) of another parent. This is called a cross. Think of breeders as really tall bees.

The difficulty lies in keeping ONLY the parent pollen on the stigma. To this end, breeders put bags around each flower to prevent foreign pollen. If you are lucky, the flower you are breeding is self-incompatible (unable to be pollinated by itself) or male sterile (makes no pollen). If not, breeders must emasculate each flower (remove self pollen). This is generally hand-done, a very labor-intensive work.

After the flowers are fertilized, the seeds begin to grow. If the cross is between 2 different species, the seeds may not grow to maturity on the plant and must be grown in tissue culture. This is a method of growing plants in a lab under sterile conditions with artificial hormones and nutrients given to them in a gel-like substance.

When the seeds are collected the results of the cross are planted and evaluated for beneficial characteristics. Often further crossing is done, either back to one of the parents, or among siblings, or to something else entirely. Once a breeder is happy with the result, the plants are trialed.

Trialing takes 2-5 years, at various locations around the country, comparing the new plant to what is already available in the marketplace. Who needs another red geranium if it isn't better than the ones already for sale?

I will add one caveat- when several breeders are working on one new thing sometimes the first to the market isn't the best and everyone gets burned. Be sure to ask at your garden center if they have had good experience with a new variety before you try it.

Next spring when you are looking closely at your favorite flowers, find the pollen and the stigma and rub them together. Who knows, it might become a passion for you, too.

Now that the gardening season is winding down, I thought we'd spend a little time on a subject near and dear to my heart. Plant breeding.

Why are there so many new Echinacea and coral bell hybrids and where did they all come from? Not to mention iris, daylilies, and new annuals every year.

Some specialty perennials have been bred for hundreds of years. In 16th century Netherlands, a few tulip bulbs and seeds were brought from Turkey to the University of Leiden. Carolus Clusius, garden curator, began breeding them, sparking "Tulipmania".

In a few short years, a pound of prized cultivars sold for thousands of dollars. Fortunes were made and lost. Almost every aristocratic family had tulips as a symbol of power and prestige.

A futures market was even started for the trading of tulips. In the 1630's the bottom fell out of the market, but the bulbs remained popular and to this day the brightly-colored spring favorites are part of the Dutch identity.

Can you imagine a garden with out impatiens? Believe it or not Claude Hope introduced the first impatiens, the Elfin series, in 1969. Impatiens were an orange weed 3-4 feet tall, native to West Africa, before Claude started working on them at his home in Costa Rica.

Sometimes new hybrids need to wait for their time to come. Three decades ago a Ball Seed salesman, who collected unusual begonias, bred Dragon Wings. The powers that be didn't know what to do with such a large, enthusiastic begonia when the fashion was for small balls of color. Perseverance paid off and today Dragon Wings begonias are one of the best sellers for PanAmerican Seed.

Daylilies and irises are primarily bred by back-yard garden enthusiasts. Search the internet and you will find hundreds of cultivars of either. Flowers with only one stigma (female part) and prominent anthers (male part) are easy targets for amateur plant breeders with limited time and space.

David Culp, a local gardening consultant, breeds hellebores and has helped to popularize this wonderful genus. His Brandywine Hybrids introduced many new colors to the Lenten Rose.

Public gardens such as the Chicago Botanic Garden and Longwood Gardens often have breeding or selection programs and have introduced plants of merit. 'Longwood Blue' Caryopteris and the Meadowbrite series of Echinaceas from Chicago readily come to mind.

Universities also have long been sources of new plants. Dick Craig at Penn State has given us the Martha Washington geraniums usually on the market today. He was also instrumental in popularizing seed geraniums. 'Husker Red' Penstemon, the Perennial Plant of the Year 1996, was bred at the University of Nebraska. Most of the land grant universities have breeding programs of some nature.

Of course, private companies introduce dozens of new perennials and annuals each year.

Next spring and summer go outside and really look at your flowers. If you like what you see, thank a plant breeder.

When was the last time that we saw so many leaves still hanging around in early November? When did so many leaves land on the ground with so little color? Blame the weather of course. I'll try to explain without more information than we need.

In our climate all plants either die or head into dormancy as frost and cooler temperatures arrive. Day length and available moisture also play significant roles. Day length is consistent from one year to the next but the other two can vary greatly.

All plant activity results from chemical activity in the plant. Perhaps a good analogy would be hormones in people.

Lack of moisture, or water stress, increases the concentration of abscisic acid, which in turn encourages the plant to shed its leaves. This offers the plant an effective way to conserve water when the growing season is ending. That explains the early leaf drop before much color appeared.

The wonderful fall colors are in the leaves from new spring growth to fall leaf drop. They are hidden by the active food-producing chlorophyll in the leaves. It is when growth slows and the chlorophyll fades that the colors appear. The significantly higher temperatures of September and most of October worked to maintain growth and delay colors.

I don't think I'm dreaming when I say that with the recent heavy rain and several frosty mornings that we are seeing better color. Unfortunately, too many leaves have already dropped to make this a banner year.

As the plant gets ready for winter, food is transferred to the roots. Woody plants also store extra water in their stems. The latter storage can be impacted by stem wounds. Thus, pruning in the fall should be discouraged. Likewise, early top removal of perennials can reduce the transfer of food to the roots.

One sidebar is that often contact herbicides are quite effective when applied in late fall. A month or so ago I mowed a small field that is polluted with thistles. Right now the thistles look lush and green.

Given what we have talked about above, the weed killer would now be quickly transported directly to the roots, unlike spring or summer applications. I sure hope I can find time to have a good-bye party for those thistles. I know of no other way short of herbicides to get rid of Canadian thistles and now is a good time to attack.

I think you can also surmise from the above that anything that encourages growth late in the season has the potential to slow dormancy and increase the risk of winter injury. The fertilizer on perennials and shrubs should cease no later than early August if you use it. The water hose should be put away given the recent heavy rain.

As you can guess, something approaching the opposite happens as spring arrives. One thought is that well-mulched soil will have a more uniform and cooler temperature than one that has no mulch. The cooler temperature will delay spring growth a bit and maybe save the plant from damage during late spring frosts.

All plant growth is cyclical and dependent on environmental conditions. Dormancy is a natural "rest" period for perennials, trees and shrubs. That time is about here.