Search This Blog

Saturday, January 26, 2013

Meristematic Tissue and Propagation By Cuttings;


Lecture: Meristematic tissue and the principles of propagation by cuttings; Pages 92-113; soil mixes for propagation
Demonstration: Different kinds of cuttings
Practical: Making cuttings

Dress to be cold and wet, but be prepared to be overheated too. It was hot here Saturday afternoon, but at 3:00 PM the sun went away and so did the heat; it became cold and damp and not at all pleasant. We can be indoors for part of the class, but if it's cold, that room is cold and most of our work will be outside.

I will make hot tea – bring your own cup!

Cuttings – Asexual Propagation **(we will use pruners today)

Medium mixes for different kinds of propagation:

Note: I use potting soil or cactus mix for almost all of my work, I do not mix specific batches of medium for most applications. It takes less time and results speak for themselves. If, however, you want to do it on your own, or you are employed by an employer who insists on being penny wise and pound foolish, these are basic mixes that are used the world over.

Basic Mix with Compost

1 part sifted compost
1-2 parts Sphagnum Peat Moss
1 part Perlite
(Note: compost provides some basic nutrients for plants and should enable a few weeks growth without additional fertilization. This mix, therefore, should
not be used for starting seeds.)

Cutting Potting Mix 1:1

1 part peat
1 part sharp sand

Seed Starting Mix 1:1
1 parts peat
1 parts vermiculite

Look at the qualities of each mix and you deduce the reasons for the ingredients – you can replace constituents with others – or arrive at a solution starting with pre-mixed soil. That's primarily what I do. I have mixed my own in the past, but to me it's more work than it's worth unless you are mixing enough material to require a bulldozer!

What is asexual propagation?
Basically, cloning – any kind of propagation that doesn't involve pollination.

Why would people want that?
Keep specific characteristics alive – perhaps easier and faster than seed, sometimes to propagate a mutant or a sport, multiply many salable or fruiting plants rapidly, overcome pest or climate problems that would prohibit planting in given environment.
Potatoes, garlic, some onions are annual food crops grown from asexual propagation.

Forms of Asexual Propagation
  1. Division - rhizomatous, perennial plants
  2. Cuttings - +/- woody perennials
  3. Grafting and budding

Types of Cuttings (The term Strike = successfully rooting a cutting... )
  1. Stem Cuttings – typical for most plants
  2. Leaf Cuttings – leaf cuttings for begonias and streptocarpus; somewhat less common
  3. Root cuttings – also not that common, but very useful when needed, i.e. Romneya coulteri and Rhus species

Many plants propagated by more than one method, method of choice is usually dictated by the season, or what one has on hand or the time fram one is working within.

Stem Cuttings (what we'll do today):

We will take cuttings from many different species and put them into LGM Cactus mix (either in quarts or gallons).... Why I do what I do....
Why one gallon? Why LGM Cactus mix? Why now?

In books instructions have you take wood usually described as
greenwood Soft (or Tender)
Semi-hard
Hard

Term is descriptive of the flexibility of wood.

Greenwood cuttings are the trickiest without a misting system and attention. Soft-wood is somewhat less tricky, but still problematic for a home gardener without a green house and misting. Hardwood cuttings work but are painfully slow and can become problematic because of the necessary attention to them. Most plants will form some roots in six weeks if handled appropriately.

The crux of the problem is water loss prior to root formation. Failure of cuttings can always be summarized as 'drying out' or 'death by thirst.' However, the growth of fungi and mosses and bacteria and the resulting rot of the cutting form the limits to keeping the plants moist until they form roots.

Controlled in my case by open air, full sun cuttings and by the use of cactus mix... Misting twice a day.
Cuttings can be bagged with plastic bag – plus and minus
Grandma's used canning jars to strike cuttings.

Meristem & the Role It Plays

Meristematic tissue found at the nodes and the cambium.

Cuttings: ideally, two nodes above and two nodes below – more does not equal better!
Limited green leaf on top
Cuttings are possible with less if that's what you have
Internodal cuttings and exposing the cambium when there is only one node...

Hormones
Overuse inhibits root formation and most plants will take without it. Use of Earth Juice OK

In taking multiple cuttings, cut bottom flat and top at a slant – cuttings will not take 'up-side-down'

If possible, take as many cuttings as you reasonably can


Cuttings today:
Goji or wolfberry is the fruit of Lycium barbarum

Gingko biloba

Vitex agnus-castus or Vitex, Chasteberry, Chaste Tree,

Root stalks  

No comments:

Post a Comment

Contents of this site, text and photography, are copyrighted 2009 through 2017 by David King - permission to use must be requested and given in writing.