Get our free book (in Spanish or English) on rainwater now - To Catch the Rain.


Jump to: navigation, search

Plant propagation

89 bytes added, 3 January
==Generative propagation (from seed)==
===Pre-sowing steps===
Stratifiying or layer stacking: some seeds require more than 1 one year of stratification (hot-cold-hot period or cold-hot-cold); others only require a short germ resting time or none at all.
pregerming Pre-germing or imbibition; soak for 24 hours in water and then plant in the soil (do not leave to germ). Placement on wet kitchen paper is also a possibility. It is done with seeds that have a long germination period (3-4 weeks), the seeds can be inbibitedinhibited. The seeds are allowed to swell up to 24 hours in water and are then layed laid out in a box with damp toilet paper, covered with a glass or foil. From the moment the seeds begin to germinate, we carefully sow them.
The sowing in full soil is done from late March. With this on site-sowing, the sowed plants are not transplanted. They are later thinned-out at the desired spacing. The sowing can be done scatted or in lines. We prefer to sow in lines because the weeding can then be done with a hoe or hoe machine.
sowing Sowing depth= 2 to 3 times the thickness of the seed; however sowing needs to be done deeper with dry weather (the deeper= the more moisture), and shallower with wet weather.
Sowing by hand done in sowing trenches that are drawn near the sowing line. For this, we use the handle of a rake or the blade of a hoe. The depth of the sowing trench is related to:
* The expected weather, with rainy weather shallower, deeper with dry weather.
* The germination period, seeds with a long germination period are sowed deeper.
Take care to not to sow with a too small spacing, the plants will then quickly compete with each other making them weaker and too lenghtylengthy. Divide the seeds on equally spaced distances.
After sowing, the sowing trench is gently filled by raking the soil over it, and slightly pressing it (ie i.e., with the back of the rake), so that the seeds make good contact with the soil. With light-based germers, the seed is pressed but little or not covered.
Note that the larger the seed; the larger the lumps of soil can be for the sowing, as the soil consolidation increases.
Internal requirements
* The seed is in good condition, if:
MorfologicallyMorphologically: all parts are present and intact
Physiologically: sufficient food reserves are present that are enough dehydrated and do not have vacuoles
* The seed must be ripe: Some seeds do not germinate in spite of favorable conditions. They must undergo a maturation process. For certain seeds, a fairly severe frost period is required (apple, pear). The reserve nutrition is be converted into assimilatable form and inhibitor compounds must have been dissolved (stratification process).
* The seed must be germamble: it needs to be capable of germing under the normal conditions. The germination is greatly reduced with the age of the seed.
** Seeds that lose germination strength quickly: food reserves stored in the form of oil or fat (coffee and oilseedsoil seeds)
** Seeds that keep their germination strength a long time: food reserves stored in the form of carbohydrates (cereals, broom)
* Due to the water penetrating the seed coat and entering the germ further via osmosis, the seed starts to swell. Under the pressure of the swelling of the germ, the seed coat starts to crack. The bursting of the seed coat allows the germ to release itself: this is the germination.
* method of germing: The root always first appears, it always grows downwards or it attempts to do so. After this, the stem appears, it is often first still bent in a sharp angle, then it will erect itself and the plume can grow. With the common bean, maple, and the spruce, the cotyledons appear above the soilsurface soil surface and then usually fall off. This is called an epigeïc germination. With the pea, rye and horse chestnut, the cotyledons remain in the seed coat below the soilsurfacesoil surface. This is called a hypogeïc germination.
* seedling: the first leaves that emergence from the plume are different from the next ones and are called youth leaves or primary leaves. They are e.g. singular, while the others are composed (Umbelliferae-ic). With dicots and gymnosperms secondary roots appear shortly after on the main root. With the monocots, this is not the case, but a number of roots appear at the base of the stem, so that the main root is no longer visible among the others, these roots are sideroots side roots (they shoot off the stem). If the cotyledons are pushed above the soilsurfacesoil surface, we call the part between the attachment point of the cotyledons and the actual root the hypocotyl axis. This is part of the stem and will thicken with some crops eg e.g., radish, turnip.
[[File:Agriculture manual 1 2 1 image 12.JPG|thumb|left|200px]]
Definition: organs that contain RV on which they can survive a resting period. They are built the same way as normal stems but usually live underground and have spare food.
6 types of derived stems:
# [ corm]: wears buds, end bud too. Few plants have such a propogation propagation form, the most famous one being the potato. Some plants also have small nodules in the axillary buds: lilies. cut in X's, fungicide
# [ Rhizome]: grows horizontally in the soil. Knots (not buds) and clearly identifiable internodes. from the nodes the above-ground shoots and roots grow. Several years old. iris, bamboo species, mint, Elytrigia repens, calla lilies, Asparagus (short rhizomes), Canna, bearded irises (Germanica), Convellaria majalis, peony, rhubarb, Polygonatum, Sanseveria, ...
Have a stem with very short internodes. The growing point is surrounded by thick fleshy leaves: scales or skirts (eg onion and tulip). Flowering bud and above-soil leaves develop themselves in the center of the bulb.
Bulbs with skirts: daffodils and tulips, fleshy and very broad leaves
Bulbs with scales: Fritillaria; no dry membranous covering scales, are very membranous and cover each other only partially. Bulbs multiply by division. With Lilium lancifolium and Lilium tigrinum: brood balls in the armpits. Propogation Propagation by planting off the scales.
====Rosettes grown out of the stem====
* Each part contains sufficient food reserves
When divisioning, we follow these steps:
The mother plants are uprooted and the excess soil is shaked shaken off. The excess in leaves is removed. Make sure that growing points, shoots and roots are not damaged. Hold the plant with both hands, the thumbs as close as possible to the breaking point. Breaking causes less damage than cutting through. If breaking is not possible, the woody or fleshy part is prepared with a knife or scissors, never cut through the roots. Torn plant parts are never allowed dry out. As soon as possible plant it out in a pot of in the open-field so as to ensure a smooth regrowth in sufficiently nutrient-rich soil. Water the plants. In sunny weather we cover the plants to fight dehydration. Among others, used with [[chives]], [[lemon balm]], [[tarragon]], [[lovage]], [[oregano]], [[sage]], [[thyme]], [[fennel]].
Widely used technique with perennials and herbs. Also used to rejuvenate the plant. Also shrubs such as Hypericum, Spiraea. Time: best immediately after flowering (new shoots). With late bloomers: divisioning in spring.
Then the cutting is placed into cutting soil as soon as possible in order to allow rooting. This can be in a cuttings box, a pot or multi-plates in which 1 cutting is placed per cell. The cutting should not be placed to deep, only the portion of the cutting that is free of leaves. The air humidity needs to be sufficiently high enough when cutting. The plant can evaporate, but does not yet have roots to absorb moisture. To counteract evaporation, the cuttings boxes or cutting plates are placed under plastic film. The cuttings are lightly moistened after the placement and are placed under a plastic foil. When the air humidity is too low, the cuttings will start to hang over. When there is much water in the air, then the cutting does not have the tendency to evaporate water. At professional companies, the cuttings are placed under water mist. With a rain pipe, a water mist is made that applies a thin layer of water over the leaves. The cutting can not evaporate. Between the cuttings, there is an electric sensor that, when the humidity is below 95%, causes the water line to start spraying.
Light and heat promote the rooting of the cuttings. The temperature in the seed box is best 2-5°C above normal cultivation temperature (17-20°C). We will have to cover the plants from the sun during periods of high solar intensity. The temperature would otherwise rise too high. After the cutting has rooted enough, we will plant it outside or in a pot after hardening off.
====[ Stem cuttings]====
Most used method,
most economicly intresting economically interesting method for many plants. 
General rule:
*cuttings of herbaceous plants in spring*cuttings of woody plants: in the resting periodeperiod.
*Choice of cuttings:
*mother plant needs to be cut back significantly to attain a a variety of young twigs
*season plays a major role: woody cuttings in spring just after the buds begin to sprout, in autumn there is less chance of success but stronger material is attained that will dry out less quickly
Vegetative propogationpropagation
Roots: by [ adventitious buds] on the roots
Root propagation: somewhat larger pieces of the root are cut into pieces, they are planted and left for some time (wound can then dry) and planted (this technique is mostly done with tuberous roots)
air Air layering: soil is put unto one-year old twigs (not with woody stems)
Bulbs: left to lie for a while until the bulbs become well visible
stem Stem cuttings: only with very young twigs
* herbal cuttings (woody plants) : (for temperate climate countries) spring and early summer (mayMay-juneJune), remark: not strong, fragile, do root rapidly* woody cuttings: late summer, fall (for non-decidious deciduous plants) or winter (for decidious deciduous plants)
types of cuttings:
leaf bud cutting (eg with vitis vinfera, ...) or stem cutting (oblique cut above the bud for the top, traight straight at the bottom)
head stem cutting is not equal to a stem cutting
cutting with a heel: the heel contains more auxines, cauing causing it to root quicker
fungicide: will slow down the rooting at temperatures above 15-20°C
a too wet space to do the cutting in is also disadvantagousdisadvantageous, plant pots also need to be placed off the ground to allow moisture to ooze out
note: stem cuttings can be cut through slightly (upto up to the cambium) at the bottom on both ends to root more quickly
head stem cutting: top of the head needs to be cut off (decays quickly)
woody cuttings: old wood needs to be cut in winter and can be planted with the head slighly slightly above the soil (eg e.g., raspberry).

Navigation menu