‘Big Blue’ Sea Holly

70719This one is no fun to handle. It is just as prickly as it looks. Yet, it is the spiny foliage and blooms that make ‘Big Blue’ sea holly, Eryngium X zabelii ‘Big Blue’, so appealing. The knobby blue thistle flowers are centered on prominently flaring grayish blue bracts that look like metallic snowflakes. The intricately lobed grayish foliage contrasts splendidly with just about any darker green foliage.

Bloom begins with summer and continues almost to autumn. The first flowers are solitary on strong stems. As they fade, sideshoots from these original stems continue to bloom with smaller but more abundant flowers. They are excellent cut flowers, fresh or dried. However, cutting the first solitary flowers with long stems removes some of the sideshoots that would otherwise bloom later.

Mature plants can get three feet tall and half as wide. Shade, even part shade, causes irregular growth that can be quite weedy. Although perennial, ‘Big Blue’ sea holly might live only a few years.

Contrary to the appearance of the bristly thistle like foliage and flowers, sea holly is in the Umbelliferae family, which means that it is more closely related to celery and carrot than it is to artichoke!

Fountain Grass

80725It was probably a good idea when it was introduced to California, but fountain grass, Pennisetum setaceum, became too much of a good thing for a few temperate regions in which it naturalizes and displaces native vegetation. Although it now works to inhibit erosion where it grows wild on the embankments of highway interchanges, it must sometime be mown because it is combustible.

In home gardens, fountain grass is more appealing if shorn back at the end of winter, and watered occasionally through the warmest part of summer. If feral seedlings need to be removed, a few may be left if they happen to grow where more plants are wanted, or to replace aging plants. Fountain grass should not be planted in regions where it is likely to naturalize but has not yet done so.

Fountain grass has narrow leaves that arch upward and outward so that the tips of outer leaves are just touching the ground. They might sag lower; or they might stand more upright. The fuzzy tan or pinkish tan flowers that bloom in summer may stand as tall as three feet. Individual plants live only a few years. The cultivar ‘Rubrum’ has striking purplish bronze foliage, and does not self sow.

Blue Plumbago

70712The delightfully clear sky blue flowers of blue plumbago, Plumbago auriculata, seem like they belong with colorful annuals or in a tailored border of colorfully blooming perennials. However, the rampant canes of mature plants are really best in the background where they have room to grow wild. The canes do not climb like vines, but can flop over other shrubbery as high as fifteen feet.

Rounded trusses of small blue flowers begin to bloom sporadically by the end of spring, and continue to bloom in phases until late summer. Supposedly, each subsequent phase should be a bit more profuse than the previous; but not all plants are aware of this. They might bloom best in mid summer, and less profusely later. ‘Alba’ blooms white. Pale foliage indicates a need for fertilizer.

Blue plumbago is not as easy to work with as it seems to be. Once established, it can grow like a weed, and really seems to take care of itself, and it is probably better to allow it to do so. It does not like to be shorn into hedges or geometric shapes as it so often is. Shearing ruins the natural form, eliminates most of the outer canes that provide bloom, and exposes sparse interior growth.

Coreopsis

80718It is a common theme. Coreopsis was a much simpler group of only a few specie and cultivars in the 1980s. There are now too many hybrids and cultivars to keep track of. They have been bred so extensively that they do not produce viable seed like the old fashioned types that can self sow so nicely, and were more closely related to the unimproved specie that would be found in the wild.

Breeding did more than expand the range of floral color and form. It combined the more impressive flowers with the resiliency of the toughest of perennial specie. Because they are sterile, some of the modern hybrids may not need to be deadheaded like more traditional types. Although tougher modern hybrids can capitalize on the sustainability fad, they can not proliferate and naturalize.

Coreopsis blooms in summer and autumn. The small daisy like flowers can bloom yellow, orange, red or pink, but traditional bright yellow is still the favorite color. Most cultivars are less than two feet tall and wide. A few can get nearly twice as tall. The most compact cultivars are only about half a foot tall. Coreopsis wants good sun exposure, and will bloom less and likely mildew if shaded.

‘Mystic Spires Blue’ Salvia

70705Once it gets started in late spring, ‘Mystic Spires Blue’ salvia has potential to bloom until autumn. It only needs older floral spikes pruned away as they fade (deadheading) to stimulate new bloom. If it gets overworked and lanky without deadheading, it can be cut back in the middle of summer to start a new bloom cycle all over. It can get more than three feet tall and almost three feet broad.

Butterflies and hummingbirds really dig the small rich purplish blue flowers that are tightly packed into the upper foot or so of the floral spikes. These floral spikes tend to lean away from the center of the plant, with the tallest on top leaning collectively in one direction or another. They look like they would be good cut flowers, but they might start to drop their older flowers after only a few days.

The deep green foliage is technically evergreen, but it does not matter. All growth should be cut back to just a few inches above the ground in winter. ‘Mystic Spires Blue’ salvia likes richer soil and a bit more water than what drought tolerant salvias want. Yet, like most salvias, it grows more efficiently as #1 (1 gallon) plants planted as winter ends, than #5. Warm and sunny exposure is best.

 

Hydrangea

80711There are so many more of the fancier cultivars of hydrangea, Hydrangea macrophylla, than there were as recently as the 1990s. Many of the pink and blue hydrangeas were interchangeable years ago. They would bloom blue if the soil was acidic. They would bloom pink if the soil was alkaline. Their color changed accordingly when planted from potting media into soil of another pH.

Most of the modern cultivars nowadays are better at one color or the other. Those that want to be rich pink or almost red might turn lavender or purple in acidic soil. Those that want to be rich blue might do the same in alkaline soil. That makes for many hues of pink, blue, lavender and purple. Most of those that bloom white always bloom white, and their foliage might be a little lighter green.

There is also much more variety in floral form than ever before, although all bloom in summer or autumn with big rounded or nearly spherical trusses of many small flowers. The deciduous leaves are about six inches long, and pleasantly lush and glossy. Modern compact cultivars stay low and dense. Larger cultivars get about six feet high and wide, with somewhat open branch structure.

Beech

70628Compared to crape myrtle, sycamore (London plane) and many other more popular trees, the beech, Fagus sylvatica, is much less problematic, and really deserves more respect. Although it can eventually get almost as big as sycamore, it has remarkably complaisant roots. It is neatly deciduous, defoliating only in autumn, without noticeable floral mess. Disease and pests are rare.

Beech is probably unpopular with landscapers because new trees are a bit more demanding than other tree specie are. (Landscapers prefer easier trees.) Until they disperse their roots, they are more likely to desiccate if they do not get watered regularly enough, and more likely to rot if watered too much. They grow somewhat slowly, so need to be pruned more carefully for a high canopy.

Those of us who tend our own gardens do not mind the extra effort for such a distinctive tree. The handsome foliage can be rich green, coppery bronze, darkly purplish or variegated with white or pink that fades to white. A cultivar with sunny yellow new foliage fades to green by summer. Most beeches have spreading branch structure, but some are strictly vertical or sculpturally pendulous.

Coneflower

80704The native American coneflower, Echinacea purpurea, of the Midwestern prairies has been popular within its native range longer than anyone can remember, and has become more popular in the West as extracts of echinacea became a fad in herbal medicine several years ago. Modern garden varieties and cultivars have been bred and hybridized for larger and more colorful flowers.

Coneflower has developed from a sturdy but relatively simple prairie wildflower into a flashy and potentially garish perennial, with white, pink, red, orange, yellow, purplish pink or pale green daisy (composite) flowers as wide as three or even four inches. The fat and bristly rust-colored centers become more prominent as the outer petals (ray florets) fold downward to form a domed cone.

The sturdy upright stems can get taller than three feet and wider than two feet, although some garden varieties are more compact. The somewhat raspy basal foliage is full and fluffy, but becomes progressively sparser higher up the stems. Some rare cultivars bloom with double flowers. New growth replaces the old annually, and with plenty of sunlight, blooms through the warmth of summer.

Mandevilla

70621Pink, red or white are the only choices. There happens to be a darker shade of red. Yellow throats are more conspicuous in white flowers. Otherwise, there is not much variation of color amongst the various mandevillas. The flowers are very similar in both color and form to those of related oleander, but are larger. Some are as wide as three inches. Small flowers can have pointed petals.

Mandevilla vines are surprisingly vigorous and sneaky. The lower portion of a mature plant may seem to be rather tame while it extends aggressively twining vines into trees above. Vines on small trellises can get congested on top. Pruning upper growth helps to even out growth and bloom. Exposed vines are likely to get killed back by frost in winter, but should regenerate efficiently.

The evergreen foliage is quite glossy. Some varieties have interestingly rippled leaves. Partial shade is best for rich green foliar color. Full sun can scorch leaves. Dipladenias are very similar to mandevillas, but are shrubbier and more compact, with smaller flowers and leaves. They are probably a better option for large pots. Sap of both mandevillas and dipladenias is caustic and toxic.

Oregano

80627It is considered to be an Italian herb, but since it was popularized in America in the late 1940s, oregano, Origanum vulgare, has become more popular in Italian-American cuisine than it is in Italy. It is now the traditional ‘pizza herb’ for American style pizza. Oregano happens to be one of the few herbs that is preferred dried rather than fresh. Only foliage is used, either before or after bloom.

Prior to bloom, foliage is low to the ground, on wiry stems. Blooming stems stand vertically as tall as two feet, with more foliage and tiny purplish flowers that are not very flashy. The flavor of the foliage on the upright blooming stems is distinct from that of the prostrate vegetative stems. The opposite leaves are only about an inch long, or slightly longer. Flavor can be variable with weather.

Flavor is also variable by cultivar. Some are spicier than most. Some are more bitter. Some cultivars were marketed to be more visually appealing in the garden than flavorful in the kitchen. ‘Nana’ is a dwarf. ‘Aureum’ is variegated with yellow. The famously flavored ‘Greek Kaliteri’ has compact growth, with atypically thick and slightly fuzzy leaves that are dark on top and purplish underneath.