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Every year the Perennial Plant Association names a garden-worthy perennial as its plant of the year. They have been doing this from the early 1990ies and have a wonderful record of picking plants that perform well in the garden and are rather easy to grow.

This year's pick is Nepeta 'Walker's Low'. Some sources claim this is a catmint. Others say it is catnip. Others say cats are finicky and are picky about their catmints or catnips. I agree that cats can be finicky and quit there.

Nepeta is a member of the mint family, so that gives you a clue about its vigor. It really is tame by mint standards, but should be given a bit of room. In my garden it probably tripled in size by the second season and after five years is about three feet across.

The plant was introduced in Europe in 1988. It was named for a garden there and the name is not related to plant size. Expect a height of 30 to 36 inches in the garden if the plant is very happy. The pot tag will probably claim it to be about half that size.

It is grown for its violet-blue flowers, long bloom period, attractive grey-green foliage, lack of pest and disease problems and low maintenance requirements. 'Walker's Low' likes well-drained soil but is tolerant of drought when established. Here I believe it is best used as a full sun plant.

The flower is violet-blue and clustered on upright arching stems. The bloom begins in mid-summer. On its own, the bloom is extended. With deadheading it will be even longer.

It's versatile in use. The literature suggests the front to middle of the perennial border, as a ground cover, in the large rock garden or cascading over a wall. I never thought of the last one but believe that would produce a great effect. I might try it to replace a wonderful shrub that I now have over a wall that is not so wonderful there because of severe winterkill each year.

If you are interested in critters, look for hummingbirds, butterflies and bees. The pest insects seem to have other likes and seldom bother this plant. It is also said to be deer and rabbit resistant.

The deer resistance goes back to the theory that deer depend largely on smell to warn of danger. Since the leaves emit a strong mint aroma when crushed, it is avoided. About rabbits I don't know, but I do have rabbits and my nepeta is still happy.

Hats off to the Perennial Plant Association for another great pick. It's been a bit since we shared that entire list. Why not next week? It's a great place for the new perennial gardener to start and would serve well as the backbone of any perennial effort.

It has been nearly nine months since the weatherman made his predictions about the winter of 06-07. I don't remember what he said. Do you?

The groundhog spoke in February, with surprising accuracy, and must be assigned some responsibility for current garden problems besides eating plants.

Personally, I prefer to wait at least a month after it ended to offer my predictions for the previous winter. It gives one time for analysis and usually yields quite accurate results.

A recent conversation with a person tied to one of the area's large public gardens confirmed what I have suspected. Last winter was strange. Plants that should have survived were killed. Plants that you would expect to have suffered, seem to have survived with little damage. He called the winter weird and I agreed.

As you remember, it did not get cold until early February. I planted some things in January and I have had numerous reposts of others doing the same with success.

The most unusual report was from someone who was given a holly as a Christmas decoration. After Christmas, he planted it. It survived and is happy. A few feet away an established similar holly died.Plants refused to assume full dormancy last fall and the juices or water in the stems of many shrubs and young trees froze when the temperatures turned abruptly colder. Look for a vertical crack in the lower stem as evidence. This usually is fatal or at least weakens the stem and shortens the life of the plant.

The winter was also quite wet. Days after I wrote about rhododendron problems I was asked about them. I quickly handed the person a copy of the paper and improved my creditability when they realized that I had written the article.

Anther report was with iris with wimpy new growth. A few questions later I suggested that they were too wet and that removing some of the mulch around them might help. The last report I had suggested that things were improving after pulling back the mulch.

I am not knocking mulch, just making the observation that it is sometimes poorly used. Mulch cools the soil and holds the moisture. That is great in a hot, dry summer but can cause problems with root rots during a wet winter and cool, wet spring.

When you mulch, delay spring applications until it has warmed. Since no one is going to do that, let's suggest that you reduce the depth and keep the mulch away from the plant stems. Fungus love moist stems and, besides, an inch or two will give the same results as four inches. One could ramble on but I think you see my point. It is a lot easier to predict a winter after it is over.

One of the first plants I added to my landscape when I built the house 16 years ago was a rather common, light purple, large flowered and leafed rhododendron. It got stuck in a corner facing directly east so it has little to fear from the winter wind or the afternoon sun.

My soil consists mostly of shale with some rather ordinary soil in the spaces between the small stones. I'm not sure my shale qualifies as a stone but it sure needs more time than I have to weather into real soil. That gives drainage, so the plant cannot complain about living with wet feet.

No questions asked, the chief problem with growing rhododendrons or the many plants in the same family is root or collar rots. You will spot this when the whole plant or a side rapidly withers.By the time you see the evidence, the damage may be irreversible and the plant lost. With root rots the key is prevention. Chemicals will treat the disease but not repair the damage the plant has. In other words, they are generally a waste of time once damage appears.

To prevent root rot, pick a site that is well drained. The heavier your soil, the tougher this gets. Heavy soil can be amended with compost or a raised bed built to mitigate the problem. Fortunately, few of us in this location have problem clay soil.

Other factors that contribute to root rot are excess watering and planting too deeply. The plants should be set at the same level they grew in the nursery or just a wee bit shallower. Also think about the source of the plant.

To my dismay, parts of the nursery industry seem more intent in chasing dollars than producing good plants. If the plant was grown with excess water and fertilizer to rush the growing process, it is a less healthy plant. Your impatience in the garden can produce the same results.

Collar rot, like root rot, is caused by a fungus and produces the same symptoms and results. Planting too deep and/or burying in mulch are the culprits here.

My old bush showed some tip dieback this year for the first time. At first I wanted to blame it on the winter but I guess I am the victim of another fungus disease. The symptoms are the sudden death of usually a small branch starting at the tip. The dead leaves will persist into the summer and if scrapped with a knife, the bark will have a reddish-brown coloration.

Remove the dying tip at least a foot below visible damage as soon as you see it. Sterilize the shears between cuts to prevent spreading the fungus. Spraying with a copper compound is also a deterrent.There are a few other minor problems that good cultural practices will generally prevent. Winter leaf curl in cold weather is normal and generally will not be a problem. The plant is just protecting itself against dehydration.

Rhododendrons and related plants are very shallow rooted. Going into winter after a long summer and fall drought can make the plant more susceptible to winter damage through dehydration. That was not a problem this past winter. For that reason, I keep a plastic five-gallon bucket with a few nail holes in it. It visits my azalea and mountain laurel plantings in the fall if the soil is powdery dry.

The basic rhododendrons and azaleas are easy if you think about the site and planting process and provide minimum care.

Several days ago I spied my grandson murmuring in delight and inhaling deeply while his nose was buried in a large lilac flower. My daughter was cutting a few stems to take to her grandmother from the yard of the house they recently purchased from her.

My mother is now in assisted living and my daughter, son-in-law and grandson have moved into the house my parents built nearly forty years ago. My daughter's goal is to take blooms from the yard to my mother on a regular basis. That won't be hard, as mother planted a wide array of bushes and perennials in the years she lived there.

The lilacs were some of the first additions to the yard and have now offered pleasure to four generations and are still going strong. That is a tract record of merit for any plant.

Mom's plants came from suckers of an old white and an old purple plant that grew on the bank near the old farmhouse. Those dated at least to my grandmother who moved here almost one hundred years ago. Those plants have fallen victim to progress after the barn burned, the township relocated the road and the meadow fence got relocated.

Today, lilacs come in a large array of colors and are still fragrant. They are still generally shrubs that are taller than we are. There are some shorter in height, which generally have smaller leaves.All are best grown as multi-stemmed shrubs and can be pruned to maintain vigor and control size. It is best to remove an occasional aging stem at the ground level. The ones in mom's yard will improve with the removal of a few ancient stems and a rescue from a set of hedge trimmers that weren't mine.

The rap on lilacs is that they bloom and have no other interest in the garden. My solution is to plant something else, too. I have nearly a dozen scattered through in large mixed shrub border. This week they are the highlight of the bed.

Secondly, they are prone to mildew. In a sunny, airy spot in an average season this generally isn't too big a problem. The goal is to locate them so that you can enjoy their flowers and wonderful fragrance without having to stare at them every day of the year.

I'm not sure that the old lilacs are readily available unless you poach them from a friend with an old house. I'm also not sure that the new additions can completely match the fragrance of the old ones.

I am sure that lilacs will bring joy to our lives for a few weeks each spring. Just ask my grandson. Well, maybe wait till next year, as he still isn't much of a conversationalist.

The answer is very little or even more likely, nothing. The question, and I'll let you pick the right words, comes as people complain about the horrible soil they are trying to garden in.

Quite honestly, in this area we are blessed with a rather silty loam soil that is ideal for most gardening activities. A few spots may have a bit more clay in it than we wish. These spots often are more poorly drained and have less air space.

If you have a clay-based soil, a bit of organic material will improve drainage and air-holding capacity of the soil. The solution is usually reached over time with manure, grass clippings, mulches, compost or even some peat moss.

If you add peat or any compost you need to mix it thoroughly into the soil. Many years ago, the advice was to make a wonderful hole for each new transplant. That idea raises the question of what happens to the roots when they grow past the edge of the wonderful hole you prepared. Do they expand as desired or remain in the small, wonderful hole?

Adding mushroom soil is often viewed as a cure for all problems. Mushroom soil is a great form of compost if it has been properly aged. Fresh from the mushroom house it is toxic to almost all plants because of the high level of salts (think fertilizer) it contains.

If you have any question about a product you may add, I offer a quick test. Plant a tomato plant in the product. If the tomato plant dies quickly you have a problem. If it lasts close to a week you have a safe product.

Another scheme is to add a few loads of topsoil on what you have. That's about the same as an arranged marriage. Over time they may function as one, but it will take time for moisture and air movement within the soil to operate between the two.

Constructing a raised bed might be one time when adding soil is appropriate. If your raised bed includes enough volume to satisfy most of the root expansion, it is a great way to garden. In new subdivisions where they strip the topsoil before building, they return a thin layer and sell the rest. You will have the same problems as stated above, but at least you will have something to work with.

I mentioned air-holding capacity of the soil a number of times. I think I read someplace that up to 25% of the soil volume should be air space. A like amount of volume is water.

Most of the garden flowers, vegetables, shrubs and trees we try to grow have very low nutrient requirements. Almost always these are naturally available in the soil. This is especially true if your lot is a former farm field.

There are a few exceptions where additional nutrients are needed. Quite honestly, the only two I can think of right now are corn and potatoes.

When it comes to soil, we are rather blessed. Too much attention, just like too much fertilizer and too much water, will cause you to wonder what went wrong in your garden.