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Apparently the wind and cold temperatures of this past winter reeked havoc with many butterfly bushes in our landscapes. It is my guess that many of us were co-conspirators in the crime with fall or late winter pruning.

The tops of my plants look terrible but I am seeing re-growth from the ground on each plant. You guessed it. I still haven't cut them back.

Winters like this past one are best handled by delaying pruning on most of our summer blooming shrubs, whether it is a cutback one like butterfly bushes or ones that just sustain tip die back. Most of our summer blooming shrubs will suffer a bit of winter die back and will require a haircut in the spring. My suggestion is always to wait, and wait until we know the extent of the damage. This year the damage was quite severe.

Another development on the butterfly bush front is the introduction of a number of dwarf varieties that were developed in Europe. It is my guess that they will begin appearing in the marketplace later this summer or at least by next season.

That could lead us to the question of why we plant butterfly bushes. After all they are starting to appear on some of the nasty lists of non-native invasive plants. The answer, of course, is that they draw butterflies because they are excellent nectar plants and who doesn't like to attract butterflies to our gardens.

On the question of invasion, I will agree that often a butterfly bush will re-seed but it is not too difficult to rouge out the unwanted seedlings. With diligence, this plant is easy to control.So we have a butterfly bush or bushes because we like to see butterflies. We are asking the butterflies to enhance our lives. What are we doing to reciprocate?

Butterflies, as you know, go through four life stages. They start as an egg, hatch into larvae, rest as a pupa, and emerge as a butterfly. If we love the butterflies, we need to learn to encourage the caterpillars that preceded them.

Each kind of butterfly larvae has its unique food requirements. If you are interested, get a good butterfly book and learn the specific food needs of some of these friends, Then add some of these to your landscape. Sure, they will chew our parsley or carrots or milkweeds or whatever, but this is a necessary part of their life cycle.

If you like butterflies, a butterfly bush will help but you also must stop squashing every large worm you see.

Several days ago I became engrossed in an article by a horticultural researcher that posed the question; are our landscaping efforts meant to give satisfaction next week or to improve with time? Should the major components of a project be judged when you lay down your tools, or, say five years in the future.

His first concern was soil. We are seeing a lot of new construction. Typically, in a new development the topsoil is stripped and sold. The construction is completed and a new layer of topsoil is spread on top.

Little effort is made to prevent compaction and protect soil structure. In fact, strip miners have more regulations about soil protection tha are imposed on builders. Only time, compost and deep tillage will address the problems of compaction and destroyed soil structure.

The common practice of adding topsoil is usually done in such insufficient quantities that it has no effect. When done in truckload lots, it is often like mixing oil and water. Structurally, an invisible line forms between the old and the new that takes years to breakdown.

If you must add, add compost and then mix thoroughly with the existing soil. If the above sounds like an old farmer talking, I plead guilty.

His other main point was plant selection. Many of the desirable trees and shrubs are cloned, which means they are grafted. That gives us really two plants in one, the roots and the plant we see above ground.

Generally this is fine, but it may raise a red flag in the distance. For example, there are ash trees that will handle sites from wet to dry. However, most ash are grafted onto a vigorous root that likes damp conditions.

The real problem here is the origin of the tree you are getting. The native enthusiasts tell us never to take a plant more that 50 miles north or south or more that 200 miles east or west. In my view the worst offense here is moving something north.

Problems will quickly occur if you select a top that sits on a root that is not suited for our cold winters. To a lesser extent, the opposite is also true if we select plants that can't tolerate our hot humid summers.

This is not an easy problem for the individual gardener to address. When buying a major component of the landscape, like a tree, I would ask its origin. Unfortunately, often you can't get an answer to this question. In today's industry one party grows the roots, one does the grafting, another grows the tree and another sells it.

There is no perfect solution to this, but I would suggest buying trees locally, hopefully from the grower. At least deal with someone knowledgeable that you trust.

The answer to our initial question about the long range results of our landscaping efforts includes many factors. Our discussion above covered two that are often overlooked.

Living where we do, we are blessed with a number of near century old private estates that have evolved into public gardens. Each has followed its own path. Some are open with a regular schedule while others are more restricted.

Of course Longwood Gardens stands out. We also have Winterthur across the line in Delaware. Both started as private estates of the Du Pont family and are now open to visitors. Just west of Lancaster there is Conestoga House, which offers scheduled openings.

Recently my wife and I had the privilege to tour Mt. Cuba, another Du Pont garden just a bit over the Pennsylvania line in Greenville, Delaware. That's near Hockessin. This one is currently open by appointment but is evolving to further its mission statement.

That statement from the recently deceased Mrs. Lammot Du Pont Copeland reads "to inspire in visitors a joyful appreciation of the beauty of native plants and gardens made from them and to bring the public to an awareness of the complexity and fragility of our natural environment through garden display, education and research."

On our visit we caught the first wave of spring flowers including bloodroots, trillium, and bluebells to name a few. I suspect that spring for the next month is a highlight of the year, but the garden also includes a native meadow garden and 57 varieties of native asters. Those, of course, are at their best in late summer and early fall.

Also, that their research and selection process has delivered a number of native cultivars into the general market impressed me.

Perhaps the most widely known is the Aster novae-laevis 'Purple Dome'. If you don't know this one, it is a compact form of the New England aster with a double purple flower. Like most asters, it likes full sun or light shade in moist, well-drained soil.

They also have worked with our native golden rods. Remember that golden rods take the rap for what ragweed does to our noses. The pollen on golden rod is heavy and must be moved by insects. It's too heavy to become wind borne and cause us problems.

Mt. Cuba's best known golden rod introduction is Solidago sphacelata 'Golden Fleece,' It's rather short, about 18 inches, and is covered with a profusion of golden spires in late summer. Again, it likes the perfect sunny, moist well-drained spot but is quite tolerant of difficult sites.

Sometimes I wonder how many of those sunny, moist, well-drained sites actually exist in the world?

A third introduction is Eupatorium rugosum 'Chocolate'. This one is grown for its deep mahogany foliage. The white flowers are an addition too. This one has groundcover possibilities.

I'll quit but I was fascinated by our guide (one of their gardeners) statement that he likes to visit the hills of the Susquehanna River to see how these plants grow in the wild so he can create a better native garden. There is a lot to see and inspire the gardener.

Several weeks ago I attended a garden seminar. One of the speakers was reported to be an expert on container gardening. I was amazed at how little we agreed.

So get ready for two opinions about container gardening. He advocated a soil mix of half topsoil and half of a high peat soil-less mix. I use a finely ground soil-less mix with a lot of bark.

My mix will dry quicker than his will. I am sure that his mix was intended to need less watering. Ceramic or cement pots are much more porous and breathe more so they will tolerate a heavier mix than will the common plastic pots that are available.

All my pots are plastic and work well with a lighter mix that dries more quickly. I might not have the same success with ceramic or cement pots.

He also uses the water absorbing crystals. He cautions to mix them in the soil before adding water. Apparently they swell vigorously when water is applied. As you can judge from the last sentence, I never use them.

Most soil-less potting mixes start out life already treated with a wetting agent. My only concession here is to add a wetting agent as we roll into mid summer. This can be accomplished with a purchased wetting agent or you can make your own.

My wife says liquid Ivory or Joy dishwashing soap are ideal candidates to make a wetting agent. Add a few drops while you are watering. I re-wet my soil about monthly, starting in July.

We did agree that the container is best if it is packed with plants. I doubt that you can overcrowd them and besides if you lose a plant or two you will still have plenty left.

One point to remember is that plants in a container will need more fertilizer than plants in the ground. Adding a bit every three or four waterings should be enough. Maybe a bit more for anything in the petunia family.

I guess that the bottom line is that he was designing a lower maintenance container for a droughty year. I am always guarding against over watering and a rainy season like last summer. Most container problems I see are caused by over watering.

The easiest way to judge a container's water needs is the weight test. Lift the pot just after watering and it should be relatively heavy. Don't water it again until it feels considerably lighter in weight.

There are two theories. Take your pick. It would be a lot easier if we knew what type of summer we will have. For me I know how to water plants. I'm still trying to figure out how to un-water them when they are too wet.

The weather is improving and a lot of gardeners are ready to strap on their track shoes. Their goal seems to be trying to get to spring before spring gets to us.

Besides pansies, it is a bit early to think about planting annuals in the ground. Given another week, if the long-range forecast is favorable, I would start to think about some of the cold tolerant annuals like snapdragons, dianthus, and cape daisies. There are others.

My suggestion is to ask the person you are getting the plants from what their temperature requirements are. The above annuals will tolerate light frost or near frost. Others of our common annuals don't get mad until it's under forty.

A few, like the tropicals, which seem to be increasing in popularity, impatiens, vine crops and peppers aren't happy under fifty. A bit warmer is better.

If your annuals are for containers, you have more options. If the container can be moved and you are willing to bring it inside on the few cold nights remaining, you can do them now. In general, you gain little by getting in a hurry.

At his point it is quite safe to plant perennials. I would inquire about their history though. There is a tendency at some garden centers to use greenhouse conditions to get summer or fall blooming perennials into flower for the spring season. These might be as tender as some of the tough annuals.

Shrubs, too, are safe with a few exceptions. Butterfly bushes are tough to over-winter in pots and thus usually get special attention over the winter that makes them sensitive to early planting. I would wait until near the first of May for them. I would use that date for ornamental grasses, too.

If trees are in your plans I can't think of any problems that may lurk at this stage of the season.

I also get lots of questions about pruning now. Do not touch your spring blooming shrubs until they have bloomed. Fall bloomers can be done now. Since many of the fall bloomers often have a bit of twig dieback in cold winters, I would not get in a hurry. Wait until you see the first green and then work accordingly.

If you have a few fruit trees, do your pruning. I might wait another week or so on peaches and nectarines, but it's ok now. On the fruit trees an oil spray soon will cover a lot of insect problems. Leaf spot on stone fruits also should be addressed now.

Spring is about here. Enjoy it but don't get into a race. >