Weekly Express-News Article
By Calvin R. Finch, PhD, SAWS Water Resources Director, and Horticulturist
Saturday, August 18, 2007
“Color on the Way”
Many of our summer blooming plants bloom until cold temperatures
arrive but there are also some special fall blooming plants that
can make a major impact in the fall landscape.
Fall asters (also called michaelmas daisies) are inconspicuous
right now but come October, they become a focal point in many
area landscapes. They grow to mounds 2.5 feet tall and six feet
around that are covered with lavender blooms for about three weeks.
The best spot for a fall aster is a hot sunny corner of the boulevard
or other location in full view. The soil does not have to be very
good and once they are established fall aster does not require
supplemental water. They will soon be available in area nurseries
with limited blooms but the real show will be in future years
when the tough plant gains some size.
Fall asters are pest-free. They die back to the roots every winter
and grow from late spring until early fall. They can be pruned
lightly to control size until mid-August and then allowed to grow
unfettered until they complete their bloom period.
Cape honeysuckle has tubular orange-red one inch flowers. The
foliage and flowers resemble trumpet creeper in miniature. Beginning
in September, they are blooming machines until the first freeze.
In addition to the color, the blooms are a favorite nectar source
for the waves of hummingbirds that visit San Antonio every autumn.
Cape honeysuckle die back every winter but can grow to 10 or
12 feet tall by September 1st. They can be used on an arbor as
a leaning vine or can be trained as an upright shrub. Cape honeysuckle
is drought-tolerant and pest-free. Grow them in full sun.
Firespike grows and blooms in deep shade. It makes an excellent
container plant or can be grown in the shrub border where it dies
back to the roots every winter. The plant is so shade tolerant
that container grown firespike can be taken into the house during
the winter where it makes a decorative foliage plant. As attractive
as the shiny green leaves are, the major show in the fall comes
from the spike of red blooms that arise a foot or more above the
foliage. Firespike is a favorite hummingbird plant for shady patios
and gardens. They are in bloom at area nurseries right now. Firespike
is not a xeriscape plant. It does best with regular irrigation.
Salvia coccinea is another fall blooming plant that can tolerate
the shade. It is very drought-tolerant and grows in the sun in
addition to the shade. The common red and a bicolor (pink and
white) version are available as container grown stock. The bicolor
is called tropical salvia. The red flowered salvia coccinea will
reseed itself in the garden or even a weedy field. It is an excellent
xeriscape plant that the deer do not eat, and is a favorite hummingbird
Purple coneflower will also naturalize for fall blooms. It prefers
full sun but is just as drought-tolerant and pest-free as salvia
coccinea. In addition to attracting hummingbirds, purple coneflower
is a favorite butterfly food source and provides seed for the
finches and cardinals. Coneflower is a part of every wildflower
seed mix or they can be purchased as large plants in containers
at area nurseries. Deer do not seem to eat purple coneflower.
Blackeyed Susan is a Rudbeckia just like purple coneflower. The
flowers resemble sunflowers with richer colored, lusher petals
and can be quite spectacular in the autumn garden, but they do
not over winter or reseed as well as purple coneflower. The “Indian
Summer” variety is just one of many showy selections. Use
blackeyed Susan for yellow fall blooms that attract butterflies.
Grow them in morning or full sun.
Mexican mint marigold makes a mound of golden yellow flowers
up to three feet tall. They are pest-free and very drought-tolerant,
but require well drained soil to prosper. Mexican mint marigold
is like fall aster in its ability to become a visual center of
the autumn landscape. Like fall aster, they require full sun to
bloom to their full potential. Mexican mint marigold has a longer
bloom period than fall aster, but they look great together. I
am not sure why they have mint in their name. They should be called
Mexican licorice marigold because they have a pleasant anise fragrance.
Autumn sage or salvia greggii is another fall blooming plant.
It also has a bloom flush in spring and has a few blooms even
in the hottest summer. Autumn sage is available in many bloom
colors including red, pink, salmon, and white. The flowers are
small and dispersed along the stem so the impact is not as great
as some of the other autumn bloomers, but they are attractive
and reliable. Autumn sage has some shade tolerance, is very drought-tolerant,
and is pest-free. It is best to cut this evergreen perennial back
to the ground every few years to prevent it from becoming too
leggy. It looks best at about 2.5 feet tall with new herbaceous
growth. Deer do not eat autumn sage.