Viewing flowering perennials in winter is always a treat, even in Los Angeles where summer weather is never more than a day or two away.
Just the other morning I got up and walked outside to see a hellebore (HELL-uh-bore) bursting with fat flower buds ready to open.
This robust specimen, growing in the shade of a lemon verbena (Aloysia triphylla) and a chaste tree (Vitex agnus-castus) has never received any attention other than occasional irrigation. It puckers out during the summer, when all of its burnt foliage is cut to the ground. It is never fertilized. But right this moment, on a hellebore no more than 1 foot square, there are 50 creamy white flowers about to open.
Hellebore (Helleborus spp.) is an herbaceous, clumping plant, so it will expand its girth from one year to the next. This really is a can’t-miss perennial for the shade garden, a fitting companion to Japanese anemones and infinitely more reliable than frequently short-lived azaleas.
No, hellebores do not appreciate hot weather but you grow them for the winter garden, where perennial color is at a premium.
Although cream and lime green are the most widely seen hellebore flower colors, you can find cultivars in pale magenta and deep burgundy, verging on black, as well.
The Balkans are home to the greatest number of hellebore species, but their habitat stretches throughout Europe and into Southwest Asia and China.
Where woody winter flowering perennials are concerned, Australia offers an embarrassment of riches. There is no better venue for viewing these beauties than the Conejo Valley Botanic Garden in Thousand Oaks. The moment you lay eyes on a spotted emu bush (Eremophila maculata), you will want one in your garden.
The genus name Eremophila (eh-reh-MOF-il-a) comes from two Greek words: eremos, meaning solitary place or desert, and philos, meaning love. The spotted emu bush is a desert lover, growing up to 6 feet tall in a garden of drought-tolerant plants. Watered more liberally, it will double in height. After it is done flowering, you may apply a slow-release fertilizer but, even if you don’t, it will still grow well. The only absolute requirement for its growth is well-drained soil.
Emu bushes attract birds and other wildlife of all types.
Among Australian woody perennial groups, however, grevilleas are the most recognized. Whether ground covers, shrubs or trees, their telltale flowers are spidery and their leaves are usually needlelike. Yet, there is still considerable diversity in flower and foliar forms.
At the Conejo Valley Botanic Garden, several grevillea representatives are in full flower. Spider-net grevillea (Grevillea thelemanniana) is a large, rangy bush with scarlet blooms and the hybrid `Robyn Gordon’ is noteworthy for its gigantic flowers. Olive-leaf grevillea (Grevillea olivacea) has yellow-orange flowers with olivelike foliage. Incidentally, the flower color of olive-leaf grevillea is remarkably similar to that of a young yellow butterfly bush (Buddleia spp.) growing in its vicinity.
And speaking of yellow, there is an interesting collection of perennial yellow penstemon (Penstemon pinifolius `Mersea Yellow’) growing along a nearby nature trail.
Grevilleas appreciate a somewhat acidic soil so regular applications of gypsum are recommended to prevent chlorosis, a condition where leaf spaces between veins turn yellow. Broadcasting a balanced fertilizer with iron is also a good idea, but be careful of products high in phosphorus since they are likely to kill grevilleas and other Australian natives.
If you are passionate about a perennial purple bloomer, but are tired of trailing lantana (Lantana montevidensis), consider the California native lilac verbena (Verbena lilacina). This carefree perennial, which is a lantana cousin, merrily sprawls wherever soil drains well. It blooms from winter until fall.
Payne’s thryptomene (Thryptomene saxicola `Payne’s Hybrid’) is an Australian woody perennial with pinkish-violet flowers that grows up to 9 feet tall. It is sometimes referred to as heath myrtle, since it belongs to the myrtle family (which includes eucalyptuses, bottlebrushes and other Australian natives), although its foliage and flowers are reminiscent of those found on heaths and heathers.
The indestructible lobster plant (Plectranthus neochilus) is resistant to heat, drought, snails and deer. It is also aromatic. Lobster plant’s purple flowers will remind you of Spanish lavender (Lavandula stoechas) blooms, which is not a coincidence since they are both in the mint family (Lamiaceae).
Sweet violet (Viola odorata) is another purple ground cover presently in bloom. Its weedy growth is a nuisance in the opinion of some, since it spreads irrepressibly by means of rhizomes and seeds, but its reliable production of flowers and heart-shaped leaves each January is a welcome sight to others.
Tip of the week
If you are fond of the long-flowering characteristic of society garlic (Tulbaghia violacea), but do not like its smell, you may want to consider a fragrant cousin of this plant. Sweet garlic (Tulbaghia fragrans) has flowers that, placed in a vase, will disseminate their delicate aroma throughout your kitchen or dining room. Sweet garlic leaves are wider but not as densely growing as those of society garlic and, lastly, sweet garlic may also need slightly more summer water than society garlic to look its best.