We will define reproduction as the ability of all living beings to beget, at some point, other beings similar to them. Reproduction can be sexual or asexual.
Sexual reproduction or generative multiplication involves fertilization, that is, the fusion of male and female gametes to produce a zygote, which when developed will form an embryo and this in turn joins a new plant. Its importance is due to the fact that in the zygote the recombination of the genetic material (usually DNA, but it can also be RNA) of both parents occurs, resulting in the new plant genetically different from each of the parents and with variable characters. (from two parents can come plants with different heights, different productive potential, different resistance to pests and diseases, etc. . ). It favors genetic variability and the evolutionary advancement of the species.
Asexual reproduction or vegetative multiplication takes place without fusion of gametes; new individuals are generated from a single parent, and are genetically identical to it and in turn to each other. The same characteristics of their parent are transmitted to the new generation, both desirable and undesirable, but this does not guarantee that all plants have the same appearance since the development of any type of character is highly influenced by the effects of the environment in which they develop. Being cloned individuals (“identical”) their uniformity is an advantage in the management of the crop. The methods of asexual propagation can be classified as natural, if they are structures of plants that allow them to reproduce asexually (bulbs, tubers, rhizomes, stolons, offspring, apomixis, etc. ) or artificial if produced by man (stake, cutting, grafting, layering and in vitro culture). From the evolutionary point of view, asexual reproduction lacks the adaptive (evolutionary) advantages offered by sexual reproduction, but allows the indefinite fixation of interesting genotypes.
Reproducing our plants is the best and cheapest system to increase the number of plants in our house and also the way to perpetuate species with rare traits or those to which we have a special affection. I am going to explain the basic principles of the different techniques so that you can see that with a little practice we can master them without any problem.
Reproduction by seeds is generally a method of sexual reproduction, although a small number of plants (such as rowans) are able to reproduce by seeds from a single individual without fertilization: it is apomixis.
The flower is the reproductive sexual organ of most cultivated plants.
The male part is called androceum, and is composed of the stamens, each stamen is formed by the filament and the anther, which is the place where the pollen is located. The female organ is known as gyneceo and is made up of: stigma, style and ovary, which is where the eggs are located. Plants, depending on the sexual organ that their flowers present, are classified into:
- Hermaphrodites; the flower has the two sexes, the male and the female.
- Monoecious; the plant has both male and female flowers. These plants generally present entomophilic fertilization (by insects) and anemophilous (by the wind) so that the male flowers usually appear at the distal ends of the branches so that the pollen when removed by the wind can be deposited on the female flowers in their downward movement.
- Dioecious; each plant has a sex. For there to be fertilization (in this case it is called cross fertilization) a male plant and another female plant are necessary. Pollination is also anemophilous or entomophilic. It is a way to avoid self-fertilization.
Within the monoecious plants these can be classified into:
- Ginoic: it has only female reproductive structures; the “female” plant.
- Androic: it has only male reproductive structures; the “male” plant.
- Gynomonoic: has hermaphrodite and feminine structures.
- Andromonoic: has hermaphrodite and male structures.
- Subandroic: plant that mostly has male flowers, with a few female or hermaphrodite flowers.
- Subgynoid: plant that mostly has female flowers, with a few male or hermaphrodite flowers.
- Polygamous: Male, female, and hermaphrodite structures all manifest on the same floor.
Likewise, dioecious plants can be classified into:
- Hermaphrodite: only hermaphrodite plants.
- Monoecious: monoecious plants only.
- Dioecious: dioecious plants only.
- Gynodioic: female and hermaphrodite plants are present.
- Androdioic: male and hermaphrodite plants are present.
- Subdioic: population mainly of dioecious plants, with a few monoecious individuals.
- Polygamous: male, female, and hermaphrodite plants are found in the same population.
Plants can also be classified, based on the provenance of the male and female gametes involved in fertilization. in:
- Autogamous; when both the male and female gamete come from the same individual. In turn, autogamy can be:
- Obligatory, when the seeds come from the gametes of the same individual. There is no evolutionary breakthrough.
- Falcultative, when the seeds can come from the same individual or from two different unrelated individuals. There may be evolutionary advancement.
- Allogamous; when the gametes come from different individuals. In turn, allogamy can be.
- Geitonogamia, is the cross-pollination that occurs between different flowers, but of the same individual -plant- or between flowers of different individuals, but genetically the same (between clones or strains).
- Xenogamy, is the cross-pollination that occurs between individuals -plants- genetically different.
Once the pollen matures, it leaves the anthers and reaches the stigma, either by wind, water, insects or birds, it produces a pollen tube that grows like this to the ovary where the fusion of the male and female nuclei occurs. The fertilization of an egg results in the formation of a seed. Inside it develops an embryo, from which all the cells necessary to form a new plant originate.
The seed consists of:
- An embryo, formed by an embryonic axis and two cotyledons. The seeds are classified according to the embryo they carry into:
- Nutritional reserves, which can be stored in a specialized tissue called endosperm or albumen, or in the embryo itself (proteins, fats, oil and hemicellulose).
- A seminal covering that covers and protects the embryo and endosperm.
Germination is the set of processes that occur from the moment the embryo begins to develop until a new seedling is formed capable of living and developing on its own, regardless of the reserves accumulated in the seed. The germination process is divided into the following phases:
- Imbibition. The water that surrounds the seed enters by osmosis into it and the embryo is hydrated and releases gibberellins. A peculiar feature of the seeds is their low water content (between 5 and 20% of their weight), which gives them their “dry” appearance; Due to this, the transport of water by osmosis to the interior of the seeds is favored.
- Digestion and transport of food. Enzymes are released that dissolve the reserve substances accumulated in the seed serving as food for the embryo (hydrolysis of starch to give glucose molecules, hydrolysis of lipids to give fatty acids, etc.).
- Cell elongation. The embryo uses the food that is at its disposal to lengthen its cells.
- Cell multiplication. Once the cell elongation phase is finished, the cell multiplication phase arrives.
- Germination. The embryo swells until one end of the embryonic axis breaks the seminal envelopes and appears clearly in our sight, giving us the first visual signal that the seed is germinating. The end of the embryonic axis that appears first is the one that will give rise to the root. Subsequently, the other end of the embryonic axis that will form the first shoot will appear.
- Seedling. It has its root and bud, but it still feeds on the reserves of the seed.
Among the factors that condition the germination process of any seed we have the extrinsic factors to the seed and the intrinsic ones.
- Extrinsic factors:
- Availability of water; it is the most limiting factor. Water has to be present in its proper measure, neither much nor little.
- For each species there is an optimal germination temperature and a high and a low temperature, above and below which the seeds do not germinate.
- In most cases the germination process of the seed is independent of the presence or absence of light (they are called “non-photosensitive”) but a small number of species need, either light or dark (positive or negative photosensitivity); those that have positive photosensitivity we must bury them scarcely in the substrate.
- Oxygen; most plants germinate smoothly in a normal atmosphere (21% O2).
- Intrinsic factors:
- Seed viability; the ability of a seed to germinate under favorable conditions once the factors that kept it at a dormancy have been eliminated.
- Germinative power; is the relationship between the number of seeds germinated and the number of seeds that were put to germinate at a temperature of 24 ° C and with sufficient and necessary humidity.
- Degree of maturation of the seed. Here we must distinguish morphological maturity (when the seed has reached the full development of the structures that form it. It does not imply that the seed can germinate) and physiological maturity (when the metabolic changes necessary for it to germinate have occurred in the seed). Three cases can occur: that physiological maturity is reached before morphological and the seed germinates while still in the plant. Morphological and physiological maturity occur at the same time so as soon as the seed detaches from the plant and falls to the ground it lends itself to germination. That morphological maturity is given before physiological maturity; These seeds will go through a more or less long period before fully developing their germinative capacity.
- Permeability of the seed to water and oxygen.
- Cleaning. Here we will distinguish two groups of seeds:
- Those that are covered with a fleshy pulp. We will cut the fruit in two, take out the seeds and put them in a glass jar. After about three days (no more than four) a white veil will appear on the surface of the container; it is a fungus and tells us that a fermentation process has taken place and that the gelatin that surrounded them has dissolved. We will pour water into the container and let the seeds decant. We will discard those that float. We will collect the remaining ones and put them to dry.
- Seeds that ripen on the plant in a non-fleshy pod or capsule. We will let them dry on the plant until the wrapper turns brown and we will collect them. We will avoid rains as much as possible.
- Drying. Fundamental process, since if we stored the wet seeds we could have problems of rotting and even germination. We must do it as soon as possible and in a place where the sun does not give and that is dry and ventilated. One way to know if they are dry is to bite them with your teeth; if they remain marked is that they are still wet.
- Storage. The storage conditions of our seeds are summarized in:
• Low humidity (dry place)
• Low temperature
• Absence of light
• Absence of heat
• Absence of oxygen
Once well dried, we will introduce it into a glass jar (ideal because it will be hermetically closed). Previously we can leave it 2 or 3 days open so that they finish releasing the possible humidity they have and we do not detect. It is ideal to incorporate inside the jar a piece of chalk or the silica bags that we find when we buy shoes. This will absorb any possible moisture that could appear inside the boat.
When 50% of the seeds we plant do not germinate it will mean that the storage life of that seed is over.
How to germinate our seeds.
Seeds only need water, heat and air to germinate. Properly treated seeds germinate without problems in a temperature range between 20 and 30 ºC (having its optimum at 25ºC) in a period of between 2-7 days depending on the species. I will describe the two most common processes to germinate seeds:
- Germination with previous soaking in water. We will immerse the seeds 24 hours, no more, in a glass of water. After 24 hours we will take them out and put them to germinate between a damp cloth or between two pieces of cotton soaked in water at a temperature of 25ºC. We will moisten the whole whenever necessary. Once the white tip of the radicle appears, we will collect them with tweezers and quickly place it in a small pot with a rooting substrate and with the root down; the aerial part of the plants has negative geotropism (it grows in the opposite direction to gravity) and the root has positive geotropism (grows in the sense of gravity, i.e. downwards). If we put the root up and the aerial part down the plant would have to make an overexertion to reverse its position with the consequent extra expenditure of nutrients and energy.
In this photograph we can see an experiment carried out with two cannabis plants which we put to germinate in a cotton and once germinated we planted the one on the left with the radicle down and the one on the right with the radicle up. The one on the right took 5 days longer to appear on the substrate than the one on the right, being able to appreciate the gap in vegetative growth that will undoubtedly be reflected at the end of the crop cycle in a lower production.
The seedling has food reserves for a few days so we will not provide fertilizer at first. Once we see that the first yellowing leaves we will begin to fertilize. We have to be very observant with this issue so as not to leave the seedling without fertilizer too long.
- Direct planting. We will immerse the seed 24 hours in water and then plant it in a rooting substrate (50% blonde peat or coconut fiber and 50% perlite or sand). We can use seedbed trays or pots that we have from when we have bought plants in the nursery, making sure to disinfect them after each cycle. The planting depth will be about twice the width of the seed.
Once in the substrate, we can put the plants under a culture light that provides dry heat (we will see the possibilities) ensuring that the temperature of the substrate is around 25ºC. We must prevent the surface of the substrate from drying out.
Whether we do it in one way or another, we must bear in mind that once the plant is in the substrate we must adapt the irrigations to the root volume; very little and spaced at first and increasing the dose and increasing the frequency with the passing of the days. We will apply the water with very fine jets to avoid the displacement of the substrate.
I recommend using distilled water for the germination of the seed that by not having dissolved solutes will favor the osmosis process and the entry of water into the seed. A water with many dissolved solutes can even dehydrate the seed.
Latency and dormition.
Seed germination is a key period for plant survival, therefore, it is not surprising that nature ensures the success of germination by means of more or less complex mechanisms. Dormancy and dormition are two mechanisms that help the seed germinate at the most appropriate times so that new plants have the maximum chances of survival. Latency ensures that the seed germinates at a time when environmental conditions are conducive to the development of the new plant. Dormition ensures the survival of the species in the face of unforeseen environmental changes, so frequent in nature. The similarity between dormancy and dormancy is its result; in both cases a viable seed cannot germinate. The difference between both situations is in the causes that originate them:
- Latency is the inability of a seed to germinate, due to the fact that the environmental conditions are not appropriate to do so. This inability is accompanied by the maintenance of viability and germinative power, which will manifest itself when these environmental conditions are conducive to germination. The types of latency are related to the extrinsic factors that condition the germination process and that we have seen above (lack or excess of water, light and temperature.
- We define dormition to the inability of some viable seeds to germinate under appropriate environmental conditions for germination, an inability that will be lost after a more or less long period of time. It is related to the intrinsic factors that condition the germination process (lack of permeability to water and / or oxygen, the embryo has not reached physiological maturity, presence of germination inhibitors, absence of germination promoters or greater proportion of inhibitors than promoters).
Interruption of the state of dormancy of the seeds.
Plants manage to maintain the state of dormancy through certain mechanisms:
- Presence of chemical inhibitors; they can be found both in the seminal covering and in the internal tissues of the seeds (embryo). Phytohormones play an important role in the germination process of seeds: gibberellins stimulate it while abscisic acid (ABA) inhibits it. Also some phenolic compounds act as germination inhibitors.
- Mechanical constraints; in many cases, seminal covers represent a real mechanical barrier to the expansion of the radicle, which is not able to break the cover to go outside. This case is very common in the so-called “hard” seeds (legumes).
Modern horticulture has developed effective methods to solve the natural dormancy of seeds so that they germinate more quickly and therefore the risk of failure is lower. Among these methods we find:
- Mechanical scarification; consists of totally or partially eliminating part of the seminal covers or causing small damage or wear on them in order to facilitate the entry of water into the seed. We can easily achieve this by sanding the surface of the seeds with sandpaper. With very small seeds we can line the inside of a matchbox with sandpaper; we will introduce them inside and shake them from half a minute to a minute.
- Stratification; we will introduce the seeds in a plastic bag, close it and store them 6 to 12 weeks at a temperature of 25-30ºC. After this stage we will immerse them in water 24 hours. We will take them out of the water, spread them on a damp cloth and store them in the refrigerator at a temperature of between 1-5ºC of 6-10 weeks. Once we see that they begin to germinate we will pass them to a small pot with rooting substrate.
- Exogenous application of gibberellins; we will prepare a solution of gibberellic acid (GA3) at a concentration of 100-500 mg/L and immerse the seeds in it for 24 hours.
REPRODUCTION BY CUTTING.
It is the most used and fastest form of vegetative or asexual reproduction. It is about reproducing a plant through living parts of it (stem, leaf or root) taking advantage of pruning it so as not to affect its state or appearance. Not all plants can be reproduced by cuttings so we must inform ourselves before starting. The best time is autumn and spring, times with a pleasant climate. In summer and winter, seasons with more extreme climates, we must place them indoors, either in a greenhouse or in a room of our house.
We will prepare the mother plant in such a way that it presents low nitrogen content and high photo assimilated content (sugars and starch); this is achieved by providing for 2 weeks prior to the cutting of the cuttings a fertilizer solution low in nitrogen and high in phosphorus and potassium. Potassium increases the flow of assimilated photos through the phloem to the storage organs (cambium).
As we have seen before, the clones will be in the image and likeness of the mother plants so we will choose those healthier and more vigorous. We will use a well-sharp and clean tool when making the cuts to select the cuttings and thus avoid the risk of disease transmission. Once the cut is done, we will introduce the part to be planted in a glass with water to avoid cavitations, that is, the appearance of air bubbles in the conductive vessels (xylem / phloem). We will not use pots or large containers since the greater the volume of substrate, the greater the difficulty in controlling the humidity; the most indicated are the black plastic pots.
We will use rooting substrate (50% blonde peat or coconut fiber and 50% perlite or sand) and apply rooting hormones. We will place the pots in a semi-shaded place, without drafts, at a constant temperature of 20ºC and we will keep the humidity constant. We will use a very dilute nutrient solution (the nitrogen provided will be 100% nitric and no ammonia) and rich in phosphorus and we will maintain a pH between 5 and 6 to avoid the proliferation of pathogens. We will avoid foliar sprays.
Meristems are groups of undifferentiated cells responsible for the permanent growth of plants because they have a high capacity for cell division and can subsequently differentiate into a wide variety of cell types. These will be the cells that, stimulated conveniently, will lead to roots emerging from a stem. It is the Auxin/Cytokinin ratio that causes meristematic cells to differentiate in one way or another:
- Concentration of cytokinins and auxins alike keeps meristematic cells undifferentiated.
- Higher concentration of cytokinins versus auxins promotes the differentiation of primary meristematic stem cells.
- Higher concentration of auxins versus cytokinins promotes root differentiation.
When we cut a stem, the areas of hormone synthesis (the apex) begin to send them to the cutting area through the phloem, but this process is slow and can take 5 to 10 days depending on the length of the cutting. We can accelerate this process by applying these hormones directly to the area of the stem that we have buried in the substrate.
The main rooting products on the market contain one, two or three of the following substances:
- 1-naphthaleneacetic acid (ANA);; 1-naphthaleneacetic acid is a synthetic plant hormone belonging to the auxin family. Like all auxins, 1-naphthaleneacetic acid is toxic to plants at high concentrations.
- 3-indolpbutyric acid (AIB);; phytohormone of natural origin belonging to the family of broad-spectrum auxins. It contributes to the development of roots in vegetables and ornamental plants, likewise its use allows to obtain larger fruits.
- 2,4-dichlorophenoxyacetic acid (ADF); hormone of synthetic origin used as a herbicide with systemic action. Used at certain concentrations, it favors the appearance of adventitious roots.
These hormones can be presented in liquid, gel or powder and can be applied directly or in aqueous solution. We must read the manufacturer’s instructions because an application of these hormones in excess causes the opposite effect to the one we are looking for in our cutting.
It is a technique widely used in the reproduction of deciduous shrubs such as hydrangea. Softwood has greater rooting capacity than those taken from harder wood. The stems are cut in early spring from the ends of the fast-growing stems and with a diagonal cut to leave more traspiration surface.
In turn we will cut a portion longitudinally of the stem to expose more cambium surface.
We will choose vigorous stems with at least four knots and cut them in the morning and immediately introduce them into a glass with water to avoid cavitations. We will remove the apical end to favor the budding of the axillary buds (eliminate the apical dominance) and remove the basal leaves.
We will apply rooting hormones in the two knots that we fence to bury and we will leave two or three pairs of leaves in the aerial part. We can also apply on the cut ends some healing paste containing copper sulfate. We will make a hole in the substrate (previously moistened) of the approximate diameter of the stem to avoid the dragging of the applied rooting hormones. We will introduce the cutting and compact the substrate around it.
These cuttings wither very quickly if we do not have them in a location with a relative humidity of 70-80% at the beginning; keep in mind that it has no root system and its potential for transpiration is very low. For this we can build a mini-winterer covering the pot with plastic; we can also reduce the leaf surface of the leaves we leave to avoid excess transpiration that ends with our cutting.
Once the rooting begins, we will begin to apply a nutrient solution diluted to 50% of the manufacturer’s dose. If all goes well we can transplant them in one or two months.
Green wood cuttings.
Unlike those of softwood, those of green wood will be taken in late spring from vigorous stems of green wood (not lignified). We must take into account taking the cuttings before flowering since the cuttings of flowering plants are more difficult to root, although not impossible. The process to follow is the same as with softwood cuttings.
These cuttings can be cut between the end of summer and the middle of autumn. We will choose stems from that same year, but they will already have some degree of lignification.
In these stems, and in order to discover the cambium, we can remove some bark around the knots to facilitate rooting. These cuttings that face the winter will need us to place them in a cabin that protects them from low temperatures and keeps the relative humidity constant. Once the following spring arrives, we can place them outside.
We will choose, as always, vigorous stems of the vegetative growth of the current year. We will pick them up in late autumn and until mid-winter (this will always depend on the latitude in which we are; the further north the sooner we will cut them). We will cut between the joint of this year’s growth and the previous year’s and remove a piece of bark around the knots.
Among all the forms of cutting we have seen, only softwood cutting and green wood will be able to bloom the following spring. Those of semi-woody and woody cuttings, unless we have them during the winter in a forced environment with artificial light and control of temperature and humidity, the following spring they will use it in vegetative growth without flowering.
I show you a cutting taken at the end of spring 2019 from a macrophilla hydrangea of the ami Pasquier variety. At the end of March 2020 and in full confinement due to COVID-19, he shows his flower buds.
Cuttings of leaf shoots.
We will take them from semi-mature stems of that year’s growth with healthy leaves and well-developed shoots and take advantage of the late summer and early fall months. We will cut above the leaf and leave 3-4 cm below the stem. We will make some incisions in the stem to expose the cambium, apply rooting hormones and plant.
It is a method of asexual reproduction consisting of stimulating a stem to emit roots before separating it from the mother plant. The best time for layering is spring. The rooted twig will be removed in the autumn or the following spring, before the new growth begins. In warm climates, for example, of the Mediterranean type, you can also layer at the beginning of autumn and separate the layering in the following spring. It should not be done in the middle of summer or winter, as they are periods of inactivity. The most important thing to be successful with the layers, as with the cuttings, is to make them with the plant in full activity, when sap circulates.
Widely used in plants whose stems can reach ground level as in jasmine. A year before we will suppress the apical dominance of a low branch of our mother plant to stimulate the budding of vigorous stems. A month before we will fertilize with a solution poor in nitrogen and rich in phosphorus and potassium to force the plant to send reserves to the area of the secondary meristem (cambium). We will perform the operation in early spring or early autumn depending on the latitude in which we are. We will choose a vigorous and flexible stem and we will squeeze the leaves of the stem except those of the apex, we will remove a piece of bark in the area of the stem that we will put underground, we will apply rooting hormones and we will bury in a substrate that can be 75% blonde peat or coconut fiber and 25% perlite.
We will keep the substrate moist. Once rooted we will cut the stem below the roots and transplant. If we have done it in spring we will have it rooted in autumn; depending on the latitude in which we are we can take it out now or if the winter is very harsh we will leave it for the following spring.
A variant of simple layering is multiple layering which consists of choosing a long branch and burying several pieces of the stem. It is widely used in climbing floors. It is important that each portion of stem has a leaf and a yolk, so you can grow and produce nutritious sap from the leaves.
This technique is very useful for plants whose branches do not reach ground level. A month before the beginning of spring we will water the plant with a solution low in nitrogen and high in phosphorus and potassium; at the end of winter we will choose a vigorous stem and in good wood condition of one year; we will remove the secondary stems and leaves leaving only those of the apex.
At 15-20 cm from the apex of the branch we will realizate a ring cut in the area that we will cover to expose the cambium.
We will surround the debarked area with moistened sphagno moss and cover with a black plastic or other material that does not let light through, sealing the upper area with a piece of rope or insulating tape and leaving an outlet in the lower area to drain the water. We will water by pricking the plastic with a syringe.
We will keep the moss permanently moist, but without flooding it. After the first two months, the paper is uncovered every 15 days to see how the rooting is going. We will have to wait until we observe a good amount of white roots through the plastic. As soon as the roots surround the plastic inside, it is time to separate the layering of the mother plant with a clean cut just below the roots. The separation time of the layer varies according to the species and conditions.
The plastic is carefully removed without crumbling the moss and root ball and planted in a pot. It is located in a cool, humid place, with light, but without sun; it is watered and waited for it to sprout. We already have a new plant.
Etiolation is a natural process that occurs in plants due to the prolonged absence of light in a specific area or in the entire plant. This phenomenon is based on the partial or total loss of chlorophilic pigments in the tissues of the stems transforming them into whitish tissues very similar to that of the roots. It is very useful to achieve asexual reproduction by aerial layering of many plants because the disappearance of chlorophilic pigments in small regions of the stem, encourage the formation of new saplings or adventitious roots. The etiolation of stems of some trees or shrubs (young) facilitates the cutting because the application of rooting hormones in these ethiolate stems, act more quickly.
It is widely used in shrubs of the genus Rubus (currant, blackberry, blackberry and raspberry). These plants are biannual and do not bear fruit the first year without the stems having an excessive vegetative growth until they reach the ground, at which time they arch. Previously we will have suppressed the apical dominance to favor lateral budding. We will bury the tip of the stem in 5-10 cm of rooting substrate. After one to two months we will have the stem rooted, at which time we will cut the stem below the root and transplant into a new pot.
In winter rest period we can the plant. In spring when the new shoots come out, we cover them with soil to favor rooting.
REPRODUCTION BY RHIZOMES, TURBELS AND BULBS.
We call rhizome a stem that grows below ground and horizontally. Each knot is capable of emitting a new stem and roots. They are able to store nutrients, so they function as reserve organs for the plant when it faces extreme conditions. They grow indefinitely.
In rhizomes the propagation is done by cutting or dividing the rhizome into sections, each of which has the capacity to produce a new shoot. As the rhizome has large amounts of nutrients stored and easily produces adventitious roots, new plants are produced with little difficulty. Each transplanted portion must have at least one yolk. When transplanting the leaves should be reduced.
The rhizomes are divided at the end of the growing season or just before it begins, that is, at the end of summer, in the autumn or at the beginning of spring.
We define tuber as a thickening of the root due to the storage of reserve substances during the summer. We will reproduce them at the beginning of spring cut into healthy tuber sections and making sure that each section contains at least one shoot.
The bulbs are a thickening of the stem. They can be multiplied by chopping or by dividing the offspring.