Live And Learn

It’s so important to learn from your garden. If you spend hundreds or thousands of dollars on plants and don’t take the time to watch them and learn from your trials and errors, all your work can be temporary and fleeting.

Learn from your plants and your garden will be forever changing and forever rewarding. And with this in mind, there are few things I’d like to share with you that my garden has taught me recently.

I adore delphiniums, but just like the hollyhocks that I wrote about for the past two weeks, delphiniums have their issues and need to be grown with these issues in mind. We’re primarily drawn to the tall and stately English hybrids (the recent New Millennium series falls into this group) and it’s hard to grow these in a garden year after year unless you replace the plants regularly and treat them more as annuals than perennials. Why? Because a tiny insidious insect known as the cyclamen mite eventually finds delphiniums and wreaks havoc on them.

This tiny, nearly invisible insect can affect the plant’s roots, stems, leaves and flowers. At one point in their life cycle, these insects live in the root zone. They then travel up the stems, and as they move and feed they can transmit a few diseases. Foliage becomes distorted and yellowed and can then develop a disease we refer to as “the blacks.”

For the final insult, the mites enter the developing flower buds and begin feeding. As, or if, the buds begin to open they are also distorted.

Eventually the mites can move through a whole garden and decimate all the delphiniums. The only treatments are strong chemicals that are only marginally effective and highly poisonous to other helpful insects.

So, after growing delphs in one of my gardens for the past five years and seeing all but a few of my plants infected, I’ve decided that for the next few years my garden will be delph-less. After about three years, the mite population will have fallen and once again I’ll be planting my favorite Black Knights and other noble hybrids. Sad, but a gardening reality.

I’ve always been interested in bamboos but until 2007 I’d never planted any in my gardens. For the longest time they had a reputation for being unruly, wandering and even damaging to structures, such as sidewalks and underground pipes.

The problem was that all you could buy were varieties that were just plain invasive and even the strongest herbicides had problems getting them under control. It’s funny though because so many gardeners have only thought of bamboos as tropical plants but the truth is that a wide range of them are quite cold hardy. In the past 15 years, though, some varieties have made it over from Asia that are quite tame.

In 2007, a grower who knew of my bamboo trepidation gave me two varieties to play with.

Fergesia,

or rufa bamboo, is native to the Sichuan province (referred to in the West as Szechuan) of China. It fits into a class of bamboos that we call “clumping,” as the roots are not supposed to wander about the neighborhood and thus it’s well behaved. Allegedly.

The clump I planted was less than a foot in diameter with pencil-thick canes. So far, so good. But three years later, the clump has quadrupled in size. While I wouldn’t refer to its habit as rampant it was not as subservient as I had hoped.

The second bamboo was

pleioblastus fortunei,

or dwarf white stripe. Well, I saw the word “dwarf” and figured I was safe but I didn’t read the next line on the label that said “running bamboo.” Me stupid.

Again, the initial plant was only a foot in diameter and the first year it did nicely holding the stems upright and colorful right through the winter. Then all hell broke loose and by the end of the third year this dwarf became quite portly. The height wasn’t an issue at all but it had grown from a 1 foot clump to nearly 5 feet in diameter. A lawyer would say I had not done due diligence and I hadn’t.

I decided to explore the underground runners and traced one for about 9 feet. My garden was in mortal danger.

The bottom line is that bamboo just doesn’t seem to be for me. I can’t figure out how to work it into my garden. And the rufa gave new meaning to “clump” while dwarf white stripe was truly dwarf vertically but quite robust and invasive horizontally.

Trying to dig them out of the garden would have left tiny root parts in the soil, resulting in an inevitable resurgence with a vengeance. So regrettably, a herbicide had to be used. Several times.

In another spot I’ve got some tall lilacs growing in a mass about 20 feet long and 4 feet wide. These tall shrubs provide the shade that allows me to grow a hosta collection to the north in a lower garden. But the area around the lilacs was nearly impossible to plant because of the lilac roots and adventitious runners. But it sure would be nice to have a ground cover under these shrubs.

Enter

galium odoratum

, also known as “asperula odorata” and more commonly called “sweet woodruff.” I’ve grown this plant before and when I owned a perennial nursery we sold quite a bit of it.

It’s a great ground cover that tolerates moderate shade and once established it needs little if any care. I planted six small pots at one end of the lilacs and within three years it traveled to the other end and completely covered the ground, looking quite wonderful. But by the fourth year it was offering to keep on moving further into the garden via its root system and it needed regular persuasion to keep within its bounds. Then in the summer of 2010, a section of the planting became infected with downy mildew making my white-flowering, green-leaved ground cover a dismal mass of wilting brown.

The lesson here was again knowing what can be invasive, and secondly recognizing the issues of homogenous plantings. When one plant variety covers a large area (Do lawns ring a bell? Bluegrass lawns?) and a disease sets in, the damage is usually widespread and potentially disastrous. The

galium

may well do in itself.

So do your homework, learn from your and my mistakes, and of course, keep growing.