Page 215 - Ebook cây cảnh Art of Bonsai

Plant care directory 215

Rosmarinus officinalis
Quercus robur English oak This slow- Overwatering is possible; to avoid this, be
growing tree is difficult but not impossible guided by the amount of foliage, the season, ROSEMARY
to ramify and reduce leaf size; it is a and the rate of the soil drying out. A fragrant species to work with, rosemary
very iconic British image. Fertilizing Azaleas are hungry plants that can combine dramatic deadwood features
will thrive on heavy fertilizing. Stop during with delicate foliage that, given the correct
Quercus suber Cork oak Similar to Q. ilex, flowering, otherwise fertilize throughout management, will create dense pads. It has
but with very rugged cork bark. the growing season. a reputation for being difficult to work with,
Transplanting/Soil Transplant as and but with care and a delicate touch it will
when required based on the integrity thrive. Native all across the Mediterranean,
Rhododendron indicum
of the soil surface. Avoid damaging the it will thrive in hot weather and requires only
SATSUKI AZALEA central root core but ensure water can basic winter protection.
A popular species for bonsai, these flowering penetrate underneath the trunk. Use Hardiness/Location Frost tender, zones 7–10.
shrubs are curiously addictive for enthusiasts, small-sized Kanuma soil and plant in Protected from hard frost, they will be fine.
despite them being somewhat horticulturally slightly larger than usual pots. Make Provide full sun in summer if it is growing
unforgiving. With a basic understanding of sure the nebari is not close to the pot actively.
their needs and a slightly different approach, walls or too exposed on top. Spring is Watering Rosemary is thirsty in summer
you can achieve success. the best time for transplanting, although heat, so do not allow it to dry out. It also
Azaleas are acid-loving shrubs that thrive it is possible after flowering. remains active over winter even at low
in a specialty soil, Kanuma, which has an ideal Pests/Diseases Spider mites, whiteflies, gall temperatures, so ensure that the soil is
pH level and water-retentive microstructure. midge, scale, and leaf gall are the biggest moist but not wet over winter.
Their roots are very fine and often become worries. Look for uneven discoloration Fertilizing Lightly throughout the growing
matted on the surface when a solid fertilizer of leaves or leaf spots. Yellowing of foliage season. Do not overfertilize.
is used. If water penetration becomes difficult, on the inside can also be chlorosis or Transplanting/Soil Delicacy is the key here;
remove the crusty layer and replace with malnutrition. the roots are sensitive and will break away if
fresh soil. Try to not disturb the roots unless Pruning/Styling Azaleas can be manipulated treated too roughly. It has very fine feeder
the soil becomes compacted. When into almost any style—even the most abstract roots so a small-particle-sized soil mix is ideal.
transplanting, try to maintain a solid root ball shapes if desired—its natural growth habit A pumice-heavy coniferous mix works well.
and refrain from digging away at the core of is to form clumps. Young branches up to Once established, try to leave it in the pot
the root ball underneath the trunk. three years old may be wired and bent but for as long as possible.
Basally dominant, the apex can weaken if once they have become lignified they are Pests/Diseases Generally pest free.
water cannot penetrate directly underneath very brittle. Hard pruning throughout the Pruning/Styling Pruning is important: internal
the trunk or if those roots are disturbed or growing season will result in many buds, foliage will die off if it is allowed to constantly
pruned heavily. Prune the apex slightly more but the best time is after new growth starts extend. Prune back only to what appears to
conservatively if there is a visible difference in spring or after flowering when all flowers be an active side bud. Do not prune back the
between the top and bottom. should be removed and branches pruned whole tree all at once, especially in summer,
It is important to maintain healthy, young back hard. Ensure new foliage has the chance because the actively growing tips are
secondary and tertiary branching; otherwise to harden off before any cold weather. See important for pulling moisture up from the
the overall vigor of the tree will suffer. Do pp.122–125 for further details. roots. Treat similarly to a juniper in pruning
not be afraid to prune the tree back hard if Propagation Cuttings are very successful. back the growth, and the results will be
it is healthy. This maintains its good health, favorable. Wiring is possible, although older
which will deteriorate if no pruning is done. Rhododendron indicum ‘Hakurei’ branches tend to be very brittle; try not to
Healthy trees can be hard pruned to no Has white flowers and small leaves. put too much movement into older branches.
foliage—within a month new buds will Propagation Cuttings usually result in
appear all over the tree. Rhododendron indicum ‘Hoshi-no- great success.
Satsuki azaleas flower in late spring or kagayaki’ Bears deep purple-colored
early summer and there is plenty of choice: flowers and small leaves.
hundreds of varieties are available in a Sageretia thea
multitude of different colors, shapes, and leaf Rhododendron indicum ‘Kaho’ SAGERETIA
sizes, and each has its own idiosyncrasies. Offers large multicolored flowers and This is a common indoor species in North
Any style and size is possible, but match leaf larger oval leaves. America and Europe. It has small oval leaves
and flower size. Certain varieties will thicken and rough bark. Tiny flowers are followed
very slowly, others very quickly. Other Rhododendron indicum ‘Kinsai’ by blue berries.
species, such as R. obtusum (Kurume azalea), Bears spidery red flowers, thin leaves, and Hardiness/Location Frost tender, zones 9–11.
are occasionally used, but the best results are tends to send out long shoots that need The ideal temperature is 54–64°F (12–18°C)
gained from R. indicum, the satsuki azalea. regular pruning. during winter, 64–75°F (18–24°C) in summer.
Hardiness/Location Hardy, zones 6–9. Protect Sageretia needs a drop in temperature
it from heavy frost. The bark is very thin and Rhododendron indicum ‘Korin’ Has pink overnight. If you keep it indoors, take care
will crack, freeze, and seriously damage the star-shaped flowers and small leaves. not to overheat but make sure you provide
tree. Provide full sun up to 90°F (32°C), then plenty of sunlight.
semi-shade during midday heat. Rhododendron indicum ‘Osakazuki’ Watering Do not allow it to dry out at any
Watering They are very thirsty shrubs, so Has pink flowers, deep green leaves, and a time of year, especially indoors. High
never allow them to dry out dramatically. very strong, bushy form. humidity is ideal.