Getting To Know Plant Propagation Techniques

Getting to Know Plant  Propagation Techniques (Part 2)

2.  Tip Layering.

The tip of a  current season’s long canes bend down and touch the ground, and the contact point with the soil produces roots.

The rooted portion is adequately covered with soil until they are separated from the mother plant and replanted to become an independent new plant. Examples are boysenberry ( ) and black raspberry (Rubus spp.)  (cane fruits).

Two methods of layering

1) Mound layering. Procedures in mound layering…

• Select the best and most suitable shoots.

• Strip two or three pairs of leaves from the lower part of  the stem.

• Make a cut into the stem to about half its thickness, just below a joint where the leaves were removed.

• Extend the cut upward the middle of the stem in longitudinal position for about 2.54 cm so that a tongue is formed.

• Keeping the cut open, bring the shoot down, pressing the tongue deep into the soil.

• Stick a layering pi over the buried stem to hold it in place but put it nearer the plant than the cut to prevent damage.

• Cover the cut portions with prepared soil forming a mound 5 – 8 cm higher than the normal soil level.

• Water the mound soaking all the soil thoroughly.

• After six weeks or a month and a half inspect the layered branch by gently lifting it to see if roots have formed.

• When the roots have sprouted, cut the branch between the rooted part and the parent plant, but leave the layered plant in place for sometimes to build up its own roots.

2) Air layering.

• Select the branch at least one year old and about pencil size.

• Make an upward cut slitting just below a leafstalk for about 3.8 cm (1.5 inches).
• Insert a twist of moss to keep the cut open.

• Place a polyethylene sheet around the cut-up part of the branch and secure  the lower end of the sheet to the branch with adhesive tape leaving the other end open.

• From the open end, pack the sheet with moist moss until the cut-up part is fully covered.

• Then wrap adhesive tape around the polyethylene sheet.

• Support the layer by tying it to another branch or bamboo cane.

• Cut the layer from the mother plant when roots are seen sticking through the polyethylene sheet.

• Remove the plastic sheet and moss carefully and plant the new plant in sandy loam soil.

• Place in shaded area and water occasionally until the new plant has fully recover to stand its own.

Runners

There are plant species that produces stolons or runners (above-ground creeping stems) in various directions. When the nodes touches the soil, roots start to grow and new plantlets arises in the nodes.

These new plantlets can be used as planting materials by cutting and digging them out.

Species that produces runners includes,: strawberry (Saxifraga stolonifera), gabi ( Colocacia esculenta), etc.

Suckers

These are adventitious shoots that arises from the horizontal roots and produces new plants.

The result of this habit is that a single original plant may produce several new plants clustered together and these can be harvested as planting materials.

Some example plants that produces suckers are:  guava (Psidium guajava), raspberry (Rubus spp. ), and blackberry (Rubus spp. ).

Crowns

This is the root-shoot junction where the lateral shoots arises from the underground parts of older stems and roots.

These new shoots may be harvested by crown division by cutting the crowns into pieces such that each piece has roots and a shoot – later to be used for planting as new plants.

Examples of crown plants are: African violet (Saintpaulia spp. ) and daisy (Dimorphotheca spp.).

Human-Aided Layering

Layering under this method involves the aid of  human being to produce new plants for planting.

Methods Used in Human-aided layering

1. Air Layering.

Also called as marcotting, air layering is done by making the  parts come in contact with the soil to initiate root development to form a new plant.

Most plants can be propagated by this methods especially woody species. A selected stem or branch is girdled at a desired section about 6 to 12 inches from the tip by removing the bark, including the cambium layer at about one inch around the stem or branch.

The open area is then treated with a rooting hormone (e.g. IBA or Hormodin #3).

After treating with root hormone, a ball of sphagnum moss or other medium is spread around the area and completely wrapped with a plastic film or aluminum foil, tying both ends of the wrapped portion with a plastic tape or any other tying materials.

Use a transparent plastic film so you can see the root formation.

After a couple of weeks and the color of the roots seems mature enough, you can cut below the wrap portion of the layer and replant in separate container or planting in the field.

2. Simple Layering.

The application of this methods involves some plants with long, flexible shoots that arises from the plant at ground level and are easy to bend to touch the ground.

Select a stem or branch about one year old, girdle or nick about halfway through the portion that will be in contact with the soil.

. Nicking or girdling the stem causes the auxins and carbohydrates to accumulate in the area of the stem or branch for quick rooting.

Dig a shallow hole about 4 to 6 inches deep near the plant base and gently curve the stem or branch such that the nicked or girdled part is positioned erectly, aided by a peg.

Ones put in place, fill the hole with a soil, cover with mulching materials, and water regularly. If the peg can’t withstand to handle the work, put a weight, like big stone on top of the mulch to make it in stable condition.

When you see some adequate roots and new plant grows, cut the layer from the parent plant and dug up to separate them ,then transfer to a container.

3. Serpentine Layering.

This method is sometimes called compound layering because several layers can be obtained from one shoot that is anchored to the ground. The flexible shoot is anchored to the soil at various sites rather than buried along the entire length.

4. Trench Layering.

In this method, the midsection of the flexible stem is buried in the soil after nicking in several places. Several plantlets are developed in this type of layering.

5. Mound Layering.

Also called as stool layering, this method is done by cutting back the mother plant close to the ground. The cut portion is completely covered with soil, increasing the mound while the shoots grows bigger.

Always water the mound regularly to hasten shoot formation. When the shoots are big enough, remove the mound and cut them off from the mother plant and transfer them to  containers for future planting.

Specialized Underground Structure.

Some plants after reaching their maturity or growing period dies and have underground food storage organs that  survive in the soil and becomes dormant.

These organs are also vegetative propagation structures that produce new shoots in the growing period.

They are grouped into classes

Propagated By Separation.

Separation is the breaking away of daughter structure from the parent structure to be used to establish new plants.

Two methods of this type

1. Bulbs.

This is an underground organ that consists of fleshy leaf scales growing on a stem tissue (basal plate). The scales wrap around a growing point to form a tight ball. Lateral bulblets, or miniature bulbs, originate in the axils of some of these scales and when developed (offsets) may be separated from the mother bulb to be planted as new plant.

The two types of bulbs are tunicate and scaly bulbs.

Tunicate Bulbs.

Also called laminate bulbs,  this type of bulb consists of concentric layers of tightly  arrange scales, with the outermost layer being dry, membranous  protective layer.

Examples are; onion (Allium cepa), daffodil (Narcissus spp.), tulip (Tulipa spp.), and hyacinth (Hyacinthus spp.).

Scaly Bulbs.

Known as nontunicate bulbs, this type lack an outer dry protective membrane, so they are more delicate and requires special  care in  handling to prevent from drying and damage.

Since the scales are  not tight but loose so they can be detached from the bulbs easily.

When the foliage dies, the bulbs becomes dormant. For future planting materials, they can be dug up, separated, cleaned of soil, then store in a cool but dry place to keep them dormant.

Harvesting is done when the top portion of the foliage turns brown by natural process to produce a good planting material. Example of scaly bulbs is lily (Lilium  spp ).

2. Corms.

This is modified stem where the food is stored in its compact stem. It has nodes and very short internodes wrap in dry scaly leaves. When corm sprouts into a new shoot, the old corm becomes exhausted of its stored food and is destroyed as a new corm forms above it.

Several cormels arise at the base of the new corm. For use as planting materials, cormels are separated from the mother corm at maturity. Examples of corms are; Crocus (Cochicum autumnale) and gladiolus (Gladiolus spp.).

Propagated By Division.

Propagation by this method is done by simply breaking the plant part or cutting along natural boundaries. In division, no such clearly defined and individually packaged miniature plants exist.

Rather, the large mass of  mother plants is strategically divided by cutting into pieces so that each piece consists of basic structures to permit development into a new plant.

When using this methods of propagation, you should treat the cut portion with fungicides to prevent rotting when planted.

Three methods of division by propagation

1. Rhizomes.

Similar to stolons (above-ground horizontally growing stem) rhizomes have nodes that produces adventitious roots that support shoots at these junctions.

This method is used for propagation by cutting dormant ones into pieces at the internodes.

Example of plants propagated by rhizomes are:  ginger (Zingiber officinale), banana ( Musa paradisiaca), iris (Iris spp. ), and Kentucky blue grass (Poa pratensis).

2. Stem Tubers.

Some plants store food underground in modified stems. These swollen ends of stems don’t have nodes but rather buds (or eyes), each of which can be nurtured to produce new plants.

The tuber is divided into sections to produce new plant. Once divided, the cut surface is allowed to dry before planting.

Example of this type is: Irish potato (Iris spp.).

3. Tuberous Roots.

This swollen roots when buried in the soil produces a number of adventitious shoots called slips. These slips can be separated and planted as a new plants.

Other tuberous roots can be propagated by dividing the crown or cluster of roots of dominant plants.

Example of tuberous are:  dahlia (Dahlia variabilis) and Sweet potato (Ipomea batatas).

Suckers

These are horizontal roots that produces adventitious shoots that arises from the roots. These new shoots are separated and propagated as new plant.

Example of suckers:  raspberry ( Rubus spp.).

Offshoots

The varieties of adventitious shoots (suckers, crown division, slips, and offshoots) that arises from the stems or roots of plants are called offshoots.

The crown on top the fruit, slips arising from axillaries buds at the base, and suckers that originate from the lower part of the stem may all be used for propagation.

Example of this type are: pineapple (Ananas comosus) and bromeliads.

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Cris Ramasasa, Freelance writer, writes about home gardening and Internet marketing tips. You can get a copy of his latest ebook “How to get started in Flower Gardening” and “Vegetable Gardening Made Easy”, and also get lots of tips, tools, Free articles, and bonuses at: www.crisramasasa.com