Agriculture Reference
In-Depth Information
original species, especially if it is under stress
(see Figure 4.11).
produce new flowering growth often from
spring into winter. All the time they are
growing larger and larger, covering the spent
blooms with a new mantle of fresh flower,
while underneath that mantle they are
becoming leggier and more structurally
unstable by the day. If left to their own
devices they will collapse completely, leaving a
gaping hole, or at the very least become a
sprawling mass of stems toped by a wisp of
foliage and the inevitable flower.
Plants with deeply coloured leaves are similar.
Their deep purple or black leaves mask the
chloroplasts beneath, inhibiting
photosynthesis.
Most often reversion occurs as a result of light
deprivation; the plant is reverting to the leaf
that will gather the most light from what is
available, that is, the wholly green leaf. When
they are grown in low light conditions, their
handsome leaves may revert to the botanically
more practical green (see Figure 4.12).
Sub-shrubs that behave in this manner (see
Table 4.4) should always be prevented from
flowering until they have developed a
reasonable structure of branches from which
to launch their flowers. Pinch out any flower
buds for at least the first two to three months
after planting (see Figure 3.7). Not only will
this help the plant establish, it will build a
dense cradle of branches that can be built on.
After that you can let them rip - for a little
while. After two months of constant flower, it
is time to call a halt. Cut back the flowering
stems to a strong side shoot, thus encouraging
The best solution is to move the plant to a
sunnier spot where it will not be so desperate
to clutch at every available sunbeam.
Sometimes reversion occurs as the result of
an unstable cultivar and no matter where it is
in the garden it will produce wholly green
leaves. The best solution in all these cases,
apart from moving the plant, is to cut out the
undesirable foliage immediately from where it
originates on the plant. That is, remove the
entire branch or stem that is carrying the
undesired leaves (see Figure 4.11).
Table 4.4
Shrubs that don't stop flowering
Ageratumhoustonianum
Alyognehuegelii
Native hibiscus
Arctotisxhybrida
African daisy
Argyranthemum
spp.
Daisy bush
Brachyscombmultifida
Diascia
spp.
Erigeronkarvinskianus
Seaside daisy
Feliciaammeloides
Gauralindheimeri
Lavanduladentata
French lavender
Lavandulapedunculata
Spanish lavender
Penstemon
Salviamexicana
Mexican sage
Verbenaxhybrida
Shrubs that don't stop flowering
It is all very well to say 'prune after flowering',
but what of those hardy stalwarts that seem to
go on forever? What about the common old
daisies and the French lavender?
As most people that value plants love flowers,
we are reluctant to interrupt such generosity
as a seemingly endless display. But interrupt it
we must.
These ground covers and sub-shrubs grow
constantly in congenial conditions. They
