Tuesday, February 28, 2012

Oh, no! It's the Return of the Cone Heads!

It's a sure sign that spring is on the way in Seattle when you begin to see these in the garden.
These pink cones are ornamental winter cabbages that are nearing the end of their life cycle and are getting ready to flower. These bolting Brassicas will keep getting taller and pointier until either the gardener pulls them out and replaces them with something else or they go to seed.

In the past, I didn't like the cone heads very much, but I'm beginning to now. Maybe it's because this particular planting looks pretty good. Or maybe it's because they match the color of my rain coat.

Thursday, February 23, 2012

The 4-Step Rose Food Program

Regardless of the type of rose you plant, it is important to remember that roses are heavy feeders. One of the reasons that many of them have severe disease and pest problems is because they are under-nourished. Stressed out plants, just like stressed out people, are more susceptible to health problems.



Here is a 4-Step feeding program for roses that was given to me years ago by a rosarian with a passion for both beautiful roses and keeping hazardous chemical use to a minimum. He has long since sold his nursery and moved out of the area. Thanks, Robert, wherever you are!

  1. In February or March, after you have pruned your roses, apply 1 cup of superphosphate to each rose in your garden. Superphosphate works better than bone meal because it breaks down faster. It builds strong root systems and improves the rose's ability to flower repeatedly over the summer. It also costs less. Use it only once a year.
  2. In March or April, apply 1 cup of alfalfa meal of 2 cups of alfalfa pellets to each rose. Some rosarians repeat this application in June. Alfalfa releases nitrogen slowly and releases an enzyme that dramatically increases the rose's feeder root system. This means that the plant can make better use of available nutrients in the soil, as well as the fertilizers you give it.
  3. Starting in April, as the soil begins to warm, apply 1/2 cup of granular 16-16-16 fertilizer, and re-apply every 4-6 weeks. Your last application should be in August. (As with all granular fertilizers, water well after application unless you have adequate rainfall to dissolve them.) This step is the core of your feeding program.
  4. In May or June, apply Epsom salts (magnesium sulphate) to your roses to stimulate new, larger canes and to enhance flower color. Use 3/8 to 1/2 cup per rose. Magnesium sulphate, combined with a complete feeding program, does a good job of rejuvenating old, tired roses. 
Along with a good feeding program, be sure that your roses get plenty of water during dry spells. They aren't as thirsty as lawns, but still - they aren't drought tolerant. Also, roses need lots of sun. There are a few, rare cultivars that will grow in shade, but most will be leggy, buggy and fail to bloom unless they are in full sun.

Tuesday, February 14, 2012

Coral Bark Maple

On gray, rainy days like this one, we welcome color in the landscape. Perhaps that's why coral bark maples (Acer palmatum 'Sango Kaku') are so popular here.
Acer palmatum 'Sango Kaku'
These bright red branches really brighten up the day - there aren't many trees that look this good without their leaves on. 

Coral bark maples belong to the big, beautiful family of Japanese maples that thrive in the Pacific Northwest. Like other members of this family, these maples do best when they have some protection from full sun, western exposures. Given part-sun conditions, they require minimal summer watering once established. 

Coral bark maples are well suited to small urban gardens. Their mature height is rarely above 25'; width can be between 15' and 20'. They have an attractive vase-shape that needs little or no pruning. Their new growth tends to be twiggy, as you see above, but a little bit of judicious thinning will shape them up nicely. 

These trees offer year around beauty. In addition to the bright, coral-colored branches in winter, they have attractive light green foliage in spring and summer. In fall, their leaves turn a stunning, clear yellow - every bit as eye-catching as the branches.

Coral bank maples are available in Seattle-area nurseries now. 

Tuesday, February 7, 2012

Heavenly Hellebores

Hellebores add an exotic touch to the winter garden. Their elegant flowers begin to emerge in late January, and depending on the variety, will continue to bloom into early spring. The three varieties seen most often in Seattle are: the Lenten Rose (Helleborus orientalis), the bear's-foot, aka "stinking" hellebore (H. foetidus) and the Corsican hellebore (H. argutifolius).

Of the three, this one, the Lenten Rose, is usually the earliest to flower in my garden. Depending on the weather, buds start to emerge in mid- to late January. Mine are in full flower now and the blooms will last until the end of February. After the blooms fade, glossy new foliage will appear. Last year's foliage will die down and can be cut away to tidy up the plant. Perhaps the most common flower color for the Lenten Rose is this pink one, but you can find white, cream, greenish, and deep purple in nurseries. It is best to buy plants in bloom to be sure you get the color you want.

Next to bloom, and also in bloom now, is the so-called "stinking" hellebore. It doesn't really stink at all - unless you crush the flowers or foliage. The creamy, greenish-white flowers are much smaller than those of the Lenten Rose and the green-black foliage is more delicate.

The latest bloomer of the three is the Corsican hellebore. The one in my garden is just beginning to show flower buds. This variety has pale green flowers and light green foliage. The leaves have serrated edges and a coarser appearance than either of the other two varieties. The Corsican hellebore also tolerates more heat and direct sunlight than either of the others.

Hellebores are easy to care for. They are shade plants and will bloom even in deep shade. The Corsican hellebore, as noted, will want a little more sun, although not full exposure. The foliage replaces itself every year; simply cut away the old leaves when they look ratty. I have seen aphids on my plants as the blooms are fading, but they don't seem to harm the plant and they tend to disappear quickly.

Monday, February 6, 2012

Taking a Stroll Through the Witt Winter Garden

For me, one of the highlights of the winter season in Seattle is visiting the Joseph A. Witt Winter Garden at the Washington Park Arboretum. We had an unusual stretch of mild weather this past week, so I was able to make my annual visit without dodging raindrops. Here are some photos:
This is the entrance to the garden, lined with red and yellow witch hazels (Hamamelis sp.) in full bloom. I wish I could somehow send you the fragrance of this garden. The air is perfumed with the scents of witch hazels and vanilla plant (Sarcococca sp.)

Here is a close up of the tiny, white, intensely fragrant flowers of Sarcococca confusa.

It might still be winter, but this garden has lots of color and contrast this time of year. Here is a yellow twig dogwood (Cornus stolonifera 'Flaviramea') with a mass planting of black mondo grass (Ophiopogon planiscapus 'Nigrescens') at its feet.

If it's flower color you are craving, here's a winter blooming Rhododendron hybrid. You will also find several Camellia sasanquas in this garden, some with pink flowers, some with white.

There are several varieties of hellebores in this garden, this one is Helleborus foetidus. It is called "stinking" hellebore because the plant leaves and flowers give off an unpleasant smell when crushed. I also saw some pale yellow Helleborus orientalis, or Lenten rose, in full bloom, and others with deep purple blooms about to open.

And here, like strings of pearls, are the elegant catkins of the native silktassel (Garrya elliptica 'Issaquahensis')

Pink cyclamen bloom at the base of a Japanese stewartia (Stewartia monadelpha), a tree noted for its beautiful bark. There are many more wonderful plants to see in this garden. If you live in the Seattle area and never visited it before, treat yourself to a stroll through this garden from late January through February. It will open your eyes and your senses to the pleasures of gardens in winter.



Thursday, February 2, 2012

A Box Full of Fragrant Winter Gardening Joy

We're having a stretch of unusually dry, mild weather this week, and it's good to be outside. I have a hundred chores to do, but before getting started, I decided go to the local nursery to buy a new pair of gloves. Of course, you know how that is... I found a few more things that needed to come home with me.

And here they are, in my little box of winter gardening joy. On the left, in back, is a tiny Daphne odora, with scented blooms about to open, which will be a lovely Valentine gift for a friend; next to Daphne is Sarcococca confusa in full, fragrant bloom; in front, on the left, a lightly fragrant, yellow 'Danova' primrose; at right, a purple 'Danova' primrose. And then, of course, there are the gloves which I shall put on now and get to work.