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RHS Level 2 Certificate
Week 14- vegetative reproduction by cuttings
Learning outcomes
1.4 Describe the sowing and aftercare of a range of seed types sown outdoors (to complete from last week)
1.1 State the role of physiological factors upon the speed and success of rooting of cuttings.
1.2 Name the types of stem cuttings.1.3 Describe the propagation of plants using a range of stem cuttings.1.4 Describe the propagation of plants using a range of leaf cuttings.1.5 Describe the propagation of one plant using root cuttings.1.6 State the environmental requirements for successful rooting of each
of the types of cutting in 1.2, 1.3, 1.4 and 1.5.1.7 Describe the equipment required to propagate plants by cuttings.1.8 Describe the aftercare required for plants raised by cuttings.
Seed propagation outdoors
Used for hardy annuals, hardy perennials and many vegetables.
Cultivation – the aim is to produce a fine tilth For ornamentals unlikely to need additional fertilizer Use of the Stale Seed Bed technique to reduce
competition from weeds Sow either broadcast or in drills – the latter makes it
easier to see which are weed seedlings. Keep watered and weeded, thin out to final spacing,
provide support and dead head ornamentals as the season progresses to prolong the display
Plant examples
Hardy annuals usually sown direct into the ground – Papaver rhoeas ‘Shirley Series’, Clarkia amoena, Centaurea cyanus (Cornflower).
Biennials often direct sown – Verbascum olympicum, Digitalis purpurea, Myosotis sylvatica.
What is vegetative reproduction?
growing a new plant from some part of an existing plant e.g. strawberry
a plant that is produced in this way is genetically identical to the original plant – it is a clone
How does it work?
Newly produced plant cells contain all the genetic information needed to make a new individual (totipotent cells)
New plant cells are made by plant meristems
They divide and under the influence of plant hormones become part of plant organs (e.g. roots)
What happens when a cutting is taken?
The cutting is taken at a leaf node, there is a large area of meristem.
The cells divide quickly and form callus
These callus cells differentiate under the influence of auxin and cytokinin and become root cells
Physiological factors and rooting success
Juvenility – ideal cutting material is juvenile Turgidity – the cutting materials cells must be
full of water. Plant Growth Regulators – Auxin and
cytokinin act together at the base of the cutting to produce roots. Using artificial auxin in power form can assist this.
Physical factors and rooting success
Material must be healthy and true to type. Cut carefully from the stock plant to avoid damage to
the stock plant – no snags. Secateurs are fine here. Use a sharp cutting knife or scalpel to prepare the
cutting – to avoid crushing the xylem and phloem in the cutting stem which will form the basis of the vascular system of the new plant.
Remember that cuttings have polarity – it matters which way up they are planted. Obvious with leafy cuttings but not so for hardwood or root cuttings.
Health and safety
The scalpels are very sharp. Take care when cutting.
Some people are allergic to the sap of some plants – use the latex gloves if you are or may be affected.
Do not get the hormone rooting powder on your skin. Use the wet wipes if you do. Do not inhale the hormone rooting powder – put the lid on when not in use.
To take a cutting (1)
Chose a side shoot from the ‘mother’ plant and cut it with the secateurs just above a leaf node about 10cm from the tip
Then cut the stem of the cutting with the scalpel on the tile just below a leaf node about 6-8cm from the tip
Remove the lower leaves with the scalpel so that the cutting has a length of bare stem and 2-3 sets of leaves at most
Dip the base is hormone rooting powder – carefully and tap off any excess. Too much auxin prevents rooting.
To take a cutting (2)
Make a hole in the compost with a dibber or pencil. Insert the cutting into the hole up to just below the bottom set of leaves.
Firm the compost round the cutting with your fingertips gently
Label
After care of a cutting
To grow a cutting needs the following: Moisture Warmth Light Oxygen Nutrients
Control of transpiration in leafy cuttings is key to success – humidity, moisture in the growing medium, shade and air temperature.
Other types of cutting
Semi-ripe cuttings – leafy; taken when the new growth has started to turn woody. Need less heat than softwood. Shrubs.
Hardwood cuttings – taken whilst stock plant is dormant. Rooted outdoors or in cold frame. Plant the right way up! Trees
Root cuttings – taken when stock plant is dormant. Plant the right way up! Herbaceous perennials
Leaf cuttings – leaf section; leaf blade (lamina); leaf petiole. House plants.
Plants for cutting types (1).
Softwood cuttings – Lavatera ‘Rosaea’, Fuschia spp. Many deciduous trees, shrubs and herbaceous plants will root by this method.
Semi-ripe cuttings- Weigela florida; Ligustrum ovalifolium; Lavendula angustifolia ‘Hidcote’
Hardwood cuttings – Salix magnifica; Populus nigra; Forsythia x intermedia.
Plants for cutting types (2)
Root cuttings – Papaver orientalis; Phlox panniculata.
Leaf petiole – Sainpaulia ionantha; Peperomia caperata.
Leaf blade – Begonia rex (whole leaf); Streptocarpus rexii (remove central vein)
Leaf section - Begonia rex; Streptocarpus rexii ; Sanseveria trifasciata ‘Laurentii’
Learning outcomes
1.4 Describe the sowing and aftercare of a range of seed types sown outdoors (to complete from last week)
1.1 State the role of physiological factors upon the speed and success of rooting of cuttings.
1.2 Name the types of stem cuttings.1.3 Describe the propagation of plants using a range of stem cuttings.1.4 Describe the propagation of plants using a range of leaf cuttings.1.5 Describe the propagation of one plant using root cuttings.1.6 State the environmental requirements for successful rooting of each
of the types of cutting in 1.2, 1.3, 1.4 and 1.5.1.7 Describe the equipment required to propagate plants by cuttings.1.8 Describe the aftercare required for plants raised by cuttings.