Archive | June, 2011


27 Jun


Knotweed (Persicaria microcephala), semi-evergreen to deciduous, 3-4 feet in height with an equal to much greater spread, sprawling growth habit, small puffs of white flowers in late summer, large pointed green or burgundy foliage, full sun to part shade, somewhat drought tolerant but prefers regular water, provides excellent foliage color.


Knotweed is a fabulous perennial, which emerges in spring with dark burgundy-red stems that form a 3-4′ tall x 4-5′ wide plant. Each stem is lined with exquisite, tricolor, chevron-patterned leaves of purple, silver, and green. From midsummer through fall, the tips of the plant are covered in tiny, white baby’s-breath-like flowers. Persicaria ‘Red Dragon’ is great in the perennial border as well as in a mixed container planting. In climates with hot nights, the intensity of the leaf coloration will not be as dramatic. Persicaria ‘Red Dragon’ is not a runner, but tips that touch the ground may root down if the soil is moist.






20 Jun

Olive (Olea), evergreen tree 20 to 30 ft. in height, dwarf varieties available, typically multi-trunked with attractive gray-green foliage, some are self-pollenating, best in full sun, drought tolerant and deer resistant, easy.

From the Mediterranean. Along with palms, citrus, and eucalyptus, olives are regional trademarks along avenues and in gardens of California and southern Arizona. The trees’ beauty has been appreciated in those areas since they were introduced to mission gardens for the oil their fruit produces.

Willowlike foliage is a soft gray green that goes well with most colors. Smooth gray trunks and branches become gnarled and picturesque in age. Trees grow slowly, typically to 25-30 ft. high and as wide; however, young ones put on height (if not substance) fairly fast.

Begin training early. For single trunk, prune out or shorten side branches below point where you want branching to begin; cut off basal suckers. For multiple trunks, stake lower branches or basal suckers to continue growth at desired angles. Large old trees can (with reasonable care) be boxed and transplanted with near certainty of survival.

Olive trees look best when grown in deep, rich soil, but they will also grow in shallow, alkaline, or stony soil and with little fertilizer. They thrive in areas with hot, dry summers but also perform adequately in coastal areas. They take temperatures down to 15°F/–9°C.

Olives withstand heavy pruning. Thinning each year shows off branch pattern and eliminates some flowering/fruiting wood, reducing the fruit crop—which can be a nuisance in ornamental plantings.

Parrots Beak

20 Jun

Parrots Beak (Lotus Berthelotii), evergreen, fast growing to 6 inches in height with a 3 ft. spread, yellow to scarlet red, parrot beak-shaped flowers bloom through spring and summer, silver-gray fern like foliage on long trailing stems, full sun to part shade, cascades, great in pots, attracts hummingbirds.

Lotus berthelotii is a perennial plant native to the Canary Islands, in the genus Lotus. It has a creeping or trailing habit, with leaves divided into 3-5 slender leaflets, each leaflet 1-2 cm long and 1 mm broad, densely covered with fine silvery hairs. The flowers are yellow to orange-red to red, peaflower-shaped, but slender, 2-4 cm long and 5-8 mm broad. This plant is either extinct in the wild or persists as a few individuals. In 1884 it was already classed as “exceedingly rare” and plant collection probably hastened its decline. Decline was most likely inevitable, however, because of lack of pollinators. The plant is obviously adapted to be pollinated by birds, but no such birds remain in the Canaries.

Lemon Tree

6 Jun

Lemon Tree, evergreen shrub or tree 4-15 ft. in height depending on variety, slow thorny growth habit, fragrant flowers bloom throughout the year, produces edible fruit, fruit ripens throughout the year, requires little water once established, best when grown in sunny location.

As landscaping plants, Lemons offer year-round attractive form and glossy deep green foliage; these trees also bear fragrant flowers and fruit that is both decorative and delicious.

Citrus flowers attract bees.

Low heat requirement makes lemons widely adapted and especially appreciated in regions where sweet oranges and grapefruit won’t ripen.

‘Dwarf Lisbon’

Plants sold under this name are simply ‘Lisbon’ lemons on a dwarf rootstock, so they top out at under 12 ft. high and wide. Fruit practically identical to ‘Eureka’, but the tree is denser. Ripens mostly in fall but has some ripe fruit all year. More resistant to cold than ‘Eureka’ and better adapted to high heat; best lemon for Arizona. There is also a seedless form.

'Eureka' lemon


This is the standard lemon of markets. Bears all year. To 20 ft. tall, with somewhat open growth; branches have few thorns. As a dwarf, it is a dense tree with large, dark leaves. New growth on both standard-size and dwarf plants is bronzy purple. Should be pruned every year or two to keep the trees within bounds and the fruit easily reachable. Can be shaped as a small tree.


Vigorous, upright, thorny tree to 20–25 ft. tall; also available on dwarf rootstock (‘Dwarf Lisbon’). Denser than ‘Eureka’, but fruit practically identical. Can be trimmed up into highly decorative small tree. Ripens mostly in fall but has some ripe fruit all year. More resistant to cold than ‘Eureka’ and better adapted to high heat; best lemon for Arizona. There is also a seedless form.


This popular eating lemon grows well in the Bay Area. Fruit is thin skinned and tangy sweet, ripens year round. Plant is 4 to 12 ft. in height. Can be grown in containers or in the ground. More productive in a sunny location.