GARDENING : Color Purple’s Just Right for the Nursery

If you’ve read even one general gardening book, you know what you should do, don’t you? That’s right--plan first, plant later.

You ignore that advice? So do I.

Planning sounds reasonable in December, when you don’t feel like planting anyway. But, come spring, when the nurseries are bursting with blooming beauties and you’re itching to get your hands dirty, then it’s a different story.

Well, buck up, fellow recalcitrants. Help is at hand. All we have to do is learn to love the color purple, insists master gardener Jan Zalba of San Clemente, and we can experiment to our hearts’ content without experiencing embarrassing results.

“(English novelist and poet) Vita Sackville-West said that all the art of gardening boiled down to was putting two plants together to see if they married, and then tossing one out if they didn’t,” says Zalba.

“Well, the nice thing about purple is that it marries with anything. There’s hardly a color it doesn’t work with--except true blue--and nature didn’t make much of that.

“So if you’re fairly new to gardening--still putting things into the gardening and seeing how they work out--using a lot of plants with purple flowers and foliage as a base is a good idea. It makes everything else you plant look better.”

Purple mellows bright colors like scarlet, orange and yellow, and, conversely, adds punch to pastels, says Zalba.

“The traditional pastel cottage garden just fades into oblivion under our hot California sun without a dark anchor,” she says. “Purple does for pastel gardens what red does for Mediterranean ones.”

A background of purple foliage can also make a small garden seem larger. “Purple recedes,” says Zalba, “so planting purple at the back makes your flower beds seem deeper than they are.”

A wide swatch of purple is also a good visual and psychological barrier to separate adjoining flower beds in totally different color palettes, she says.

A useful color, this purple.

There is no shortage of purple plants to choose from in creating a secure base for experimentation in your garden. (“God must have loved purple; he made so much of it,” Zalba says.) But following are some suggestions from two gardeners with lots of experience in working with the color.

One is Zalba, a gardening instructor at South Coast Botanical Gardens in Palos Verdes for the last 17 years, and also founder of a private gardening class, the Fanatic Gardeners, based in Sierra Madre. The other is Mary Lou Heard, owner of the perennial specialty nursery, Heard’s Country Gardens, in Westminster.

One of Zalba’s current favorites for the back of the border is smoke tree (Cotinus coggygria “Royal Purple” ), a large deciduous shrub tree with dramatic burgundy-purple leaves that look particularly stunning backlighted by the rising or setting sun.

Zalba saw Cotinus for the first time in England, where it is frequently used as a dark backdrop to set off pale roses. Back home, Zalba was determined to find a specimen for her own garden and finally succeeded at Murietta Oaks, a desert specialty nursery in Murietta.

“What a desert plant like Cotinus is doing in gardens all across foggy old England I’ve never been able to figure out,” says Zalba, “but it seems to do fine there.”

The smoke tree has the potential to grow to 25 feet--and almost as wide--so the one in Zalba’s moderately-sized border will be pruned back sharply each year, which will undoubtedly shorten its life. But she can live with replacing her Cotinus periodically, says Zalba, because “there’s nothing that sets off pink roses better, and I love pink roses.”

A more easily contained background plant is bronze fennel, which looks like a heather-hued cloud come to rest.

“It’s the most soothing, restful color,” says Zalba.

Not so its flowers, though, which are a rather Screaming Yellow Zonkers hue. Zalba snips off the offenders as soon as they appear. If your taste runs to the pastel, you might want to do the same.

Bronze fennel is a snap to grow and can be found in any nursery, says Zalba. The only trick to it, she says, is allowing sufficient room. “It’s hard to imagine that little plant in its 3-inch pot shooting up to 5 feet in one season, but, believe me, it will.”

Cut back the fennel early each spring, Zalba suggests, and let it regenerate, and divide or replace when it outgrows its location.

Heard of Heard’s Country Gardens has three additional recommendations. If you have room for it, she suggests, nothing is more spectacular than Buddleia davidii (the common butterfly bush), especially the midnight-purple “Black Knight” cultivar.

“Its flowers are the most magnificent color--like the dark Midwest lilacs--and it stays in bloom until the weather turns cold,” says Heard. “It’s spectacular-looking.”

Another show-stopper is Heliotropium arborescens “Black Beauty,” she says. Though heliotrope can admittedly be a tricky plant to established here (it doesn’t like our wet winters), if you succeed, says Heard, you have a knockout. Heliotrope’s foliage has a dark purple cast and its cluster flower heads are deep violet. “It’s the clearest, prettiest purple you can imagine,” she says. Like the butterfly bush, heliotrope blooms as long as it’s warm.

Solanum rantonnetii, an evergreen vine with true purple flowers and yellow centers, is less tricky. “It’s easy to grow and you can find it at any nursery,” says Heard. Though the S. rantonnetii can be grown as a vine, ground cover, or pruned into a shrub, Heard likes it best trained into a small patio tree.

“The more you prune it, the more blooms you get,” she says. “The Solanum we have here (at the garden) have so many flowers right now you can hardly see the foliage. And the trees bloom practically year-round.”

When you move to the middle of the flower bed, the salvia family should be your purple backbone, says Zalba. There are so many salvias on the market, covering the gamut from red-violets, through true purples, to blue-violets, that selecting just a few cultivars is nearly impossible. Nevertheless . . .

Salvia haemetodes “Purple Majesty” is one Zalba and Heard agree on.

“I like it because it’s a deep, vivid, true purple,” says Heard. “It has no other shades in it.

“And because the hummingbirds love it. They go from tube to tube along the stalks. And, if one isn’t open, they knock on it with their bills to make it open.”

Zalba likes the way the plant’s tall 36-inch stems weave through other plants. “Again, I really love pink roses, but, let’s face it, all that pink can be monotonous. ‘Purple Majesty’ leaning into the shrubs and weaving its way through canes gives pale roses some needed drama.”

If you prefer the bluer side of purple, try S. haemetodes “Indigo Spires,” S. “May Knight,” or any of the S. farinacea cultivars, suggests Zalba.

A beauty on the red-violet side of purple--and another favorite of Heard--is Mexican bush sage (S. leucantha), a graceful 4 - foot plant with silver-gray foliage and velvety rose-purple flower spikes blooming summer through fall.

Then there are the lavenders, another rapidly growing family, and an excellent choice for a drought tolerant garden. L. angustifolia “Hidcote,” with its silvery leaves and deep purple flowers, is one of the prettiest and is also richly fragrant. L. angustifolia “Munstead,” dwarf with deep lavender-blue flowers is another good choice.

A new ornamental oregano both Heard and Zalba are excited about is Origanum laevigatum “Hopley’s Purple,” though neither has yet to see the plant’s reddish-purple flowers in bloom.

“I have seen lots of other origanums in bloom, though,” says Heard, “and I have yet to see one that didn’t have gorgeous flowers. But this is the first purple one I’ve heard of. I can’t wait to see it.”

At the front of the border you can’t go wrong with purple pansies, says Zalba. “They’re the quickest fixer-upper I know of.”

If somehow you end up with something like the fire-engine-red flowers of scarlet sage next to dainty pale pink snapdragons--not exactly a match made in heaven--”put some deep purple pansies between problems like that,” says Zalba, “and they’ll both look better.”

Another annual Zalba likes for the front of the flower bed is the purple-leafed versions of the culinary herb, basil.

“It looks great between pink geraniums,” she says. “It would also be splendid between these new pastel pansies on the market.”

Heard agrees: “Oh, that does sound pretty, and I’d try to find the ‘Purple Ruffles’ cultivar. It has the most decorative foliage.”

Another edging plant both Heard and Zalba concur on is catmint or Nepeta, though they like different cultivars. Zalba likes Nepeta “Six Hills Giant.”

“It’s one of my very favorite plants,” she says. “I love the way its gray-green foliage and soft purple flowers billow out about three feet all around, spilling out onto the grass and weaving their way through the legs of taller perennials, like penstemon, behind them. I find that totally charming.”

Heard likes catmint’s floppy growth habit, too, but prefers Nepeta mussinii, for its more compact form and its unusual periwinkle blue flowers.

Both gardeners claim roaming cats have been no problem with their catmint plants, but if the Nepeta you plant is destroyed by the neighborhood feline population, Zalba suggests sticking a thorny 6-inch cuttings from rose canes among the foliage--a definite cat turnoff. Lengths of bamboo barbecue skewers would do the trick, too, says Heard.

The purpleness continues: There are purple grasses (such as Pennisetum rubrum) and purple ground covers (such as Ajuga) and purple-flowered vines (such as some of the splendid clematis).

You may already love purple. Heard clearly does.

“I love lavenders and periwinkles and the deeper purples all mixed together,” she says. “That’s really exquisite. Purples play off each other so beautifully.”

But you don’t really have to love purple to learn to appreciate it. Despite singing its praises, purple isn’t Zalba’s favorite color.

“I’m more of a pink person,” she concedes. “I just ended up with so much purple in my garden because it makes all my pink things look prettier.”

Like it or not, says Zalba, you can’t afford to ignore the color purple.

“Purple is the great modifier. It softens, dramatizes, deepens, corrects. It looks good with practically anything. Every gardener needs it. It’s just too useful to be without.”