Sowing:
Sow at any time of year, ideally at temperatures of around 15-21°C (60-70°F)
Sow
in trays or pots of ericaceous (Lime free) compost, cover seeds with a
sprinkling of sieved compost and place in a propagator or warm place.
Maintain an optimum temperature of 20-25°C (70-75°F). Germination
usually takes 21-60 days.
Growing:
Transplant
seedlings when large enough to handle into 7.5cm (3in) pots. Pot on as
required. Provide a temperature of 13-18°C (55-65°F) through the winter.
Plant
in light to moderate shade, preferably with minimum competition from
tree roots. Gardenias resent root disturbance. They also grow well in
pots.
Cultivation:
Top dress plants every spring, add plenty of organic matter, such as compost or ground bark, to as large an area as possible.
Apply
a monthly fertiliser from mid march and again in late June to encourage
faster growth of young shrubs. Feeding will also encourage it to
flower, remember to choose a feed that’s designed for ericaceous plants:
an acid plant food, fish emulsion or blood meal. Do not fertilize in
the autumn, doing so will stimulate tender growth, which may be killed
in winter.
Water
plants with rain or distilled water to help reduce lime build-up in the
compost. Drip-irrigating the shrubs will keep water off the foliage and
blossoms and prevents leaf spots. Regular watering is necessary after
blooming also to keep the plants in good condition and able to withstand
winter weather.
Aftercare:
Proper
temperatures are necessary for a gardenia to bloom fully. The ideal
temperatures would be 18-22°C (65-70°F) during the day and 16-20°F (60-
62°F) at night. Gardenia needs a constant good light source to produce
many flowers. Bud drop is a common problem, it is usually occurs when
plant isn't provided with enough light or a poor draining media is used.
Gardenias are cold-sensitive and during severe winters can be killed to
the ground, but often regenerate in spring.
Pruning:
Prune
shrubs after they have finished flowering to remove straggly branches
and faded flowers. They can be pruned as far back as you like, but leave
some leaves to feed the root system. Cut plants back when they are
dormant. This way you can still enjoy flowers the next year.
If
you only want your plant to become bushier, simply pinch out the tips
while the plant is dormant. This will promote a heavier bloom the
following year.
If you are
growing your Gardenia as a potted plant indoors, keep it out of direct,
hot sun, and allow it to only get bright light.