Sow fresh seed during spring in a well drained media, keep moist and maintain a temperature of 19º to 27º C. (66º to 81º F). Plantlets take 3 to 4 years to come to flower.
Divide the clump from winter to early spring and reduce the foliage by 50%.
Propagation by Seed (General)
Germination
In order for a seed to germinate it must fulfil three conditions.
1. The embryo must be alive (a viable seed).
2. The seed must have no dormancy-inducing physiological, physical or chemical barrier to germination; also the seed must be nondormant.
3. The seed must have the appropriate environmental requirements, water, temperature and oxygen.
The interaction between these requirements and dormancy is complex and may lead to different environmental requirements that avoid the dormancy of a seed.
Sowing Seeds in Containers
There are two general methods for germinating seeds.
1. Sowing seeds in a flat or germinating bed, through which seedlings are pricked-out then, transplanted into another flat with wider spacing or directly to an individual pot.
2. Sowing seeds by placing them in to flats with the appropriate spacing or into individual pots.
This method is normally carried out with medium to large seeds such as woody plants and plants that are difficult to transplant.
Seedling production normally occurs in a greenhouse / glasshouse, cold frames and on hot beds.
Method of Seed Sowing
Fine seed is sown in pots or flats that are no deeper than 70 to 80 mm. using a sterilised well-drained media (soil). Fill the container to 20 mm from the top and sprinkle sieved peat to 3 mm depth.
Press the media down level and firm with a piece of timber and then thoroughly moisten.
Mix the fine seed with washed sand and then sow thinly on the surface. These may be lightly covered with sand.
Larger seeds may be covered with media or a hole is dibbled and the seed is placed in the media.
Watering Methods
For watering you may either mist the containers from above or place the container in tepid water and allow the water to raise through the pot to the surface of the media, then drain away and do not fill to the top of the container.
Place a piece of glass over the pot and store in a protected warm environment (glasshouse).
Seeds germinate best in darkness so shade the containers if in direct sunlight.
After the seedlings have sprouted remove the glass and ease the seedlings into direct light.
When the seedlings are large enough prick them out and transplant into larger containers and place them in a shade house to harden off.
Many seeds have different methods of seed preparation for germination such as nicking or cutting the seed coat to allow water penetration, also placing seeds in hot water and allowing it to cool off.
This is particularly important as it is softening the seed coat.
Layering (General)
Factors associated with layering.
1. Nutrition.
The stem is still attached to the plant and the intact xylem supplies water nutrition. To initiate roots on an intact stem requires certain factors.
2. Stem Treatments.
Adventitious roots are induced by the interruption of downward flow of nutrients and organic material from the leaves. Roots occur as if it is a cutting.
3. Light Exclusion.
The best results occur with the stem continuously being covered with rooting medium.
Blanching; the covering of a stem that has already formed.
Etiolation; the growing of the stem (elongating) due to the absence of light.
Both of these methods are employed either singularly or together and may require phloem interruption to induce root formation.
Physiological Conditioning
Timing of root induction normally occurs at the end of the growing season as the carbohydrates are moving towards the roots.
Root formation depends on, continuous moisture, ample aeration and a moderate temperature in the rooting area.
Uses of Layering
1. To propagate plants that is naturally layer.
2. To propagate plants that doesn't root easily as cuttings.
3. To produce a large-size plant in a short time.
4. To produce a small number of good size plants with minimal propagation facilities.
Methods of Layering
Tip Layering
This method is used on plants that produce long arching canes. The tips of these canes are placed into a hole that is sloped on one side towards the plant. This is method is carried out towards the end of the growing period. The shoots are buried facing the blunt end of the hole.
The etiolated shoot form roots and a new vertical shoot occur.
Simple Layering
This type of layering is carried out during early spring with dormant one-year-old shoots or during autumn with mature new growth.
The branches are bent over to the ground and pegged in a hole. Root stimulating may be induced with, girdling, wiring, bending and notching.
The roots are produced through the first season and may be severe and lifted during autumn or the following spring.
It is advisable to stack the emerging shoot to maintain a good shaped plant.
Compound or Serpentine Layering
This is a simple layering method where the flexible stems are covered and exposed then covered again. This will produce several plants from the one branch.
Air Layering
This method is used to propagate tropical and sub-tropical plants. It is carried out during spring on the previous season's growth or in tropical conditions after the first new leaves are produced.
First; girdle or remove the bark on the stem about 20 mm (¾ in) long and ensure that the phloem and cambium is removed. Place sphagnum moss over the exposed branch and then covered with a piece of polyethylene film so that the folds join is facing down. The two ends are twisted around the branch and tied or taped up the branch so the water cannot seep in.
Aluminium foil may be also used for this procedure. The layer should be left till autumn, though this will depend on the growth rate of the plant.
When removing from the parent plant reduce the top part of the foliage in relation to the root size then pot up and place in a moist humid environment (misting bench). Harden off in a few weeks.
Mound Layering
This form of propagation is used in the production of rootstocks for, apple, pear, quince and gooseberries. The mother plant is planted in a small trench in rows one year before layering takes place.
The next spring the plants are cut back to ground level. Three to five shoots appear and when they reach 15 cm (3/5 in) a mixture of sawdust and loose soil is mounded half way up.
This action is carried out twice more, when shoots reach 30 cm (1 1/8 in) and during mid summer. In all cases the mounding should not exceed half the total hight of the shoot. Girdling 6 to 8 week into the growing period will encourage Roots to occur in the mound.
Layered shoots are cut away from the mother plant during autumn and planted in a nursery row.
Trench Layering
This is a form of layering used for woody plants that are difficult to root in mound layering. The method involves the mother plant being planted in a trench on a 30 deg. angle one year before layering.
The following year the plant is bent over and pegged in the trench flat. As new vertical shoots appear during spring they are systematically buried before the buds swell with a rooting medium of peat or sawdust soil mix. This causes etiolation and a second layer of medium should be applied to the shoots before the buds expand.
When the shoots reach 20 cm (¾ in) a final layer of medium should be applied.
At the end of the season the rooting medium is removed and the rooted shoots are cut from the mother plant.
Natural layering
Runners
These are stems that grow horizontal from the mother plant and form new plants from a node that form its own root system. When these daughter plants root up in the soil they are dug up and planted as a new plant.
Stolons
These are modified stems that grow horizontal to the ground or under the ground with nodes that can produce new plants as in a potato tuber. These can be cut away from the mother plant and form a new plant.
Offsets
This is a lateral shoot that forms from at the base of the mother plant. Often referred to in bulbs as bulblets or lateral branching in monocotyledons, which appear as thickened stems and are removed close to the main stem. These natural methods are slow but microporpagation in aseptic culture has greatly enhanced production.
Suckers
The true meaning of a sucker is a shoot that comes from an adventitious bud on the roots, but generally it is referred to any shoots that arise from the crown of the plant. A sucker may be also seen as any shoot on a rootstock that is below the grafted section.
The method of removal is to dig out and cut it away from the mother plant with some roots attached to its base. It is then treated as a cutting, potted up and kept moist. This operation is normally carried out during the dormant period of the plant.
Crown Division
The crown is the part of the plant at the surface of the soil where new shoots arise. With lateral shoots the crown of some plants requires division when they become crowded.
Herbaceous perennials and multi-branched woody shrubs may develop large crowns that need dividing.
It is a simple method of propagation that is used by amateurs and professionals for a small increase in plants.
Plants that flower during spring to summer are divided during autumn and if flowering in summer to autumn they are divided in spring. The crown is dug up and cut with a knife in to sections, which has a shoot and abundant roots then planted or potted up. The crown may also be divided in some species by using a shovel to cut and dig sections out.
