Layering .....a technique of artifical plant propagation (Air layering ...is in the syllabus)

Layering is a technique to induce adventitious roots on a stem while the stem is already attached to the mother plant .

Types of Layering:

Layering are of eight types:

(i)  Simple

(ii) Compound

(iii)Serpentine

(iv)Air

(v)Mound/Stooling

(vi)Trench

(vii) Drop and

(viii)Tip Layering

The techniques of each type is discussed below :

Simple Layering:

(a) Time :Early Spring  ,Stem to be used : One year old which is easy to bent .

(b) One yr old stems are bent to make "U" -like structure 15 -20 cm away from the tip.

(c) The base of the "U" is pegged down and covered by soil to induce rooting .

(d) In the next Spring the stem is cut off behind the rooting portion.

Compound Layering:

(a) At first mother plants are planted 1.8 to 3 mt apart in the permanent nursery beds .

(b) The entire shoot is laid down horizontally on the soil , pegged down  and covered by rooting media .

(c)Within a year new roots will appear from each node along with new shoots.

(d) After removing the soil/rooting media a cut is made in between each node and then planted as new individual one .

Serpentine Layering:

(a)In this case only the different nodes of a flexible stem is covered by rooting media/soil .

 (b) In the next year each node with new roots & shoots will behave as propagule .

Air Layering:

(a) At first the stem is girdled by removing a strip of bark 1.8 to 2.5 cm wide around the stem.

(b)Then the cut area is covered by a mixture of moist Sphagnum / or other media & IBA , thus a root ball is made .

(c) Now the root ball is wrapped by 20 to 25 cm wide polythene film .

(d) If possible then regularly the root ball is moisted , within few months new roots will appear and in the next season the stem is cut off below the rooting portion an planted in proper place .

Mound Layering :

(a) The top of the mother plant is removed above  the ground level and covered by rooting media just before the growth begin.

(b) When new shoots are arising their bases are then covered by soil in regular interval to make it 16 to 20 cm deep .

(c) Within the next season new roots are formed .

Trench layering

(a) Mother plants are brought down to the horizontal trench and pegged .

(b) Buds are covered with about 2.5 cm of soil and then saw dust of about 5 to 7.5 cm and soil of 15 to 19 cm height are added respectively .

(c)At the end of the season soots with roots appear,then saw dust is removed and layers with roots cut off .

Drop Layering

(a) A healthy and  well branched plant is planted in a trench/hole .

(b) Whole plant is covered 100% by rooting media.

(c) From the base of the older branches new roots arise .

(d) Prior to the next seasen the plant is dug out and rooted branches are seperated.

Tip Layering

(a) Branch /shoot tip is burried in a hole having rooting media.

(b) In the next season new roots arise  below the tip of stem  and a new  erect branch tip arises .

(c) At last rooting layer is cut off from the mother plant .