The technique of sowing is, except concerning certain stages for very small seeds (see for that the section devoted to this type of sowing here ) or for very large seeds and some rare exceptions, always more or less the same. They are these various general stages, from preparation of seeds to the first transplant after germination. Approached below.

Viability
of seeds and steeping

Nonviable seeds are often the cause of a failure at the time of sowing.
The seeds can have died because not fertilized at the time of the natural process or when they are too old or when they were badly preserved before sowing.
It should be also known that the lifespan of a seed is very variable, depend on the species and the technique of conservation. Certain seeds have one very short lifespan (ex: Cacao-tree - a few days) of others several years (ex: Baobab tree - approximately 10 years). It is not the size of the seed which determines its lifespan.
One can test the viability of a batch of seeds by carrying out the steeping which is also often advised before sowing, except for the too fine seeds which it would be difficult to sow once wet (see for that the section devoted to this type of sowing here ).
It is important to try to control the viability of seeds, but it is not always possible, for example for seeds too light or small and there are also certain species whose even fresh seeds float naturally (they are often transported by the rivers in their natural environment).
To place seeds in a bottle filled with tepid water, 30°C approximately, and to let them soak jusqu ' so that they run at the bottom of the bottle. They can run immediately but that can also take several hours.
For average seeds with grosses, after waiting being able to go jusqu ' at a few hours, those which are viable run and the dead ones float. But attention! it may be also that certain still alive seeds float and it is wise to then separate those which float of those which run and to sow them separately
One can let soak seeds even afterwards during 12-24h, but more the seeds are small less it is necessary to let them soak a long time.
An important advantage of the steeping and that it avoids the problem of an incomplete humidification of possible seed at the time of a sowing without preliminary steeping and which can have as a consequence a smaller percentage of germination.
After steeping, one recovers seeds (through sieve then if those Ci are small) and sowing starts to be strictly accurate.

The container

Self made "container"
- the two parts of "A" are stuck with standard adhesive Pattex. - the part "B" is covered outside with aluminum foil. - not to forget to practise holes of drainage in the part "B"

The choice of the container with sowing depends on several factors, like the quantity to be sown (several thousands of seeds or some), the size of seeds, the time chosen between the lifting of sowings and road repair, etc. It is thus necessary to think so that one decides to make after the lifting of seeds, to let them grow more or less a long time or to mend them in another medium. One can have very well the choice according to his way of working or his means of culture.
- a generally allowed rule wants that more the seeds are large plus volume available must be large: one does not make in theory germinate a coconut in a die to be sewn!
- It is generally preferable not not to disturb the very young plants too much thus to envisage a minimum of volume nevertheless so that the plant can develop a sufficient radicular system until the next transplant.
- To envisage on average a minimal depth equalizes with 10 times the thickness of seed.
- It is not obligatory to use material sophisticated for sowings, according to the type of seed one can make very well with a yoghourt pot, one limps of sardine, a fast small boat of meal, the bottom of a plastic bottle of which the cut out top can be used to create a mini greenhouse, etc. With each one to choose according to the number of seeds to sow by species, their size, the depth necessary for the development of the roots, etc.
- In practically all the cases, it is very important to pay attention so that the container is bored at the bottom so as to let the water excess escape. In the low side part it is good also to bore some holes if the holes of the bottom are stopped or although the bottom "sticks" too much to the surface on which one poses sowing.
- the pots with sowing sold in the trade are especially useful when one sows many seeds of the same species or similar species, but it is necessary to avoid sowing in the same pot of the species which do not have the same rate/rhythm of growth or not the same development or of the different requirements out of water.

The medium

One finds in the trade what is called "Compost for sowing" but it is not obligatory to acquire that to carry out its own sowings.
- the medium must be draining so that oxygen penetrates and seeds did not rot easily.
- the mixture [ ground of garden + coarse sand ] in equal volumes is completely suitable for the majority of sowings

Filling of the Container

The container must be filled but not too much so as to preserve some place for:
- the thickness of seeds
- the thickness of the layer which is covering the top of seeds.
- the height necessary to the development of the plant after germination.
- If a lid is put, the height necessary to the development of the first leaves until the withdrawal of the possible lid.
- To set out medium homogeneously.
- To pack slightly and level with a flat object such as melt of glass, limps of matches, knife blade etc this to be able to place seeds in a regular way.

Placing the seeds

The seeds will be distributed in a homogeneous way, if possible remotely equalizes one of the other.
- Distance advised between two seeds: from 3 to 6 times size of seed at least.
- For too small seeds or "in dust", to see the section devoted to this type of sowing.
- the position or the orientation of seed in space generally does not have a major effect on germination, nature making the things well. However if you note that the seed with tendency to take a position rather than another, why not?...

Overlaying the seeds

In the majority of the cases it is necessary to cover seeds.
- Thickness advised for covering: 1 to 1,5 times size of seed
- Pack slightly, the goal being to avoid the "bubbles" around seeds.
- For too small seeds or "in dust" (cactus, Kalenchoes, etc), to see the section devoted to this type of sowing.

Medium humidification

This point is very important because a badly made humidification can compromise a sowing. Water should not be too cold nor too heat (30°C is a good temperature).
The humidification of the substrate can be made either before the placement of seeds or once the covered seeds:
1 Before the placement of seeds:
This way is operated if the seeds are too light or too small and that there is risk of displacement of those Ci at the time of watering or humidification. In this case the substrate can be sprinkled before compressing and the surfacing or humidified by steeping in a bath. Thereafter after placement of seeds and covering it is wise to supplement humidification by brumisation of the added layer of substrate.
2 After the placement and the covering of seeds:
It is the general case when the seeds are sufficiently heavy to remain in place during this operation. In this case two manners of operating at least are possible: watering by the top or the steeping of the container in a water bath.
- watering over is faster but more delicate to operate and more random because the distribution of water is not systematically homogeneous. But it allows in certain cases, for example when one does not wish that the totality of the volume of substrate is humidified, to control the rate of humidification of the substrate by proportioning water.
- watering by steeping is easiest to operate: it is enough to place the container in a water bath a maximum height equal to the depth of the substrate (it to avoid drowning sowing). For observation of the increase of water to the surface of the substrate (it changes "color"), it is necessary to let at least drain the whole during a few minutes, one or two hours if possible. One can for that slightly lean with dimensions container to cause an acceleration of the drainage in excess. It is important to let well drain not to have a saturation of moisture in the substrate.
A council which can appear useful sometimes: I often add a little soap of crockery in water rather than to operate with chemical treatments or other treatments sterilizing the substrate, than I do not advise besides.

Packing of sowing

Once the humidified substrate and the sown seeds, it is often advised to cover the whole with a bag or a hermetic lid as long as the seeds did not germinate.
This for several reasons among which:
- That makes it possible to avoid forgetting to sprinkle sowings and reduces the workload considerably.
- watering being relatively delicate as long as the plants are not established, one avoids the risks.
- the mini greenhouse thus created is most of the time favorable to germination by maintaining a humidity and a temperature homogeneous.
- the draughts are avoided which are likely to cool surface suddenly and to compromise the success of sowing thus.
It is preferable to choose a transparent cover to be able to control germination without opening.
One can also place all sowing in a closed plastic bag, but pay attention to have drained well front.

Waterings after sowing

Some prefer not to cover sowings for various reasons (oxygenation of the substrate, rinsing necessary of seeds like effect of rain, etc.): they do not have completely twists in my opinion, but the risks of lapse of memory to sprinkle, excess or insufficiency of watering, draining of the substrate between two waterings and other risks are not then to neglect...

Temperature of medium until germination

This point is certainly one of most important and yet generally neglected and majority of the echecs cause it!
The average temperature will determine at the same time the rate of germination and the speed of lifting of sowings.
It is important to understand well that the tropical plants do not germinate exactly under the same conditions of temperatures as the plants of moderate countries.
That to hear like "average temperature"?: it acts of the average between the maximum temperature during the day and the minimal temperature during the night. This variable average temperature according to the species, some being able well to germinate with 24°C of average, others not germinating with less 28°C of average, but for a maximum success of the very great majority of the tropical species, the ideal is of approximately 28°C.
The variation in temperature between the day and the night can be, like often in tropical country, of approximately 10°C.
EXAMPLE: Minimal temperature the night 23°C + maximum Temperature the 33°C day = average temperature 28°C
It is not a question either to make cook seeds, and an excessive average temperature (40°C or more) can compromise the lifting of the majority of the species.
It is thus important for a better success to control the ambient temperature near sowing.
For that one can place at with dimensions:
- a Thermometer of environment giving the minimum and the maximum reached
- a Thermostat which will light your possible electric auxiliary heating when the selected temperature is not reached: one finds the very suitable ones with less than 10 Euros in the garden-centers or hardware, (see pictures below)

Thermometer giving the maximum and the daily minimum

Thermostat connected upstream of the heating electric and allowing to control the temperature

Storage of container until germination

Where to place sowing?
- Contrary to certain ideas, sowings do not need light, and succeed better in not very enlightened places.
- In winter, one can place sowing near a heating or close to a radiator, not directly above if not place a wood board between the container and the radiator. One can also get a mini heating greenhouse in garden-center, it is a very practical tool. If not there also exists of heating resistances type of terrarium or aquarium to be placed for example in a pot filled with ground under the container at sowing.
- In summer, if the average temperature corresponds to what was indicated higher, one can make sowings in outside, but it should absolutely be prevented that the sun directly reaches sowings, the risks being then large burns or of excessive temperature.
- It is wise to also know that an interesting site is the top of a refrigerator, rather towards the back with the top of the radiator since that Ci releases a little heat.

Time for germination

Should absolutely be become aware that the times of germination depend mainly, once acquired humidification, average temperature which must be high. Patience is one of the rules of the success and one can too often compromise a sowing by handling it for example, by changing it place or while opening to observe if the seeds germinate.
For this reason, a transparent cover is useful, but it is preferable to place sowings in a dark place until germination.
Under ideal conditions of temperature and moisture, the time of germination is of a few days to three weeks, but certain species take much more time (ex: Traveller-tree, Palm tree bottle).

During sprouting and first growth

It is dangerous to intervene as of the appearance of the first plants, because the opening of sowing or its displacement can compromise the lifting of other seeds in the course of germination. It is thus advised to still wait a few days until the great majority of seeds raised before disturbing in anything sowing.
With rare exceptions close, as for example if one notes beginning of rotting (cast iron of sowing) and that it is necessary then to intervene to save what can still be it, it is not advised to intervene as long as the plants did not develop at least two true sheets yet (those which follow the cotyledons, CAD the first or the first two "sheets" which are not actually).
It is thus preferable to wait until the plants are sufficiently robust with handling before proceeding to the first road repair. For this reason it is necessary to think of well distributing seeds at the time of sowing so as to delay the moment of road repair as well as possible.
Certain sowings can thus remain in place during many months, even of the years (for example cactus or pachypodiums).
The interest of road repair is real only if the plants grow quickly or obstruct the ones the others, or if the rate of germination of the species being random, one sowed many seeds on little place (and that sowing is successful than envisaged more...)
Below examples of sowings "good to transplant", in varied containers.

A: Adeniums // B: Pachypodiums lamerei // C: Pachypodiums baronii // D: Agaves

Preparing the transplant

When the moment had just mended the seedlings, it is important to envisage well the requirement in volume necessary for each seedling, not to transplant in neither a too small nor too large container (pot or sachet), in the first case it will quickly be necessary to start again, in the second one occupies of the place unnecessarily.
It is also good before transplanting to acclimate the plants to their new environment in gradually (over a few days - weeks) placing them towards more light until if possible leaving them a few days under the conditions illumination-temperature in which they will be after transplant.
Road repair is one rather delicate moment because the seedlings undergo a more or less important stress and it is necessary to avoid of the martyriser unnecessarily. The radicular system (radicular) must the least possible be disturbed and touched.
For leaving them their substrate, it is necessary well to have prepared the pots in which one will place them.
An interesting technique of transplant consists with:
- Estimate the number of seedlings to transplant and prepare and fill the consequently pots with the substrate being appropriate for the selected species. In general a mixture with share equal in volume of ground of garden and a compost of neutral repotting "for house plants" sold in the trade is appropriate rather well. Caution! compost question the least expensive is not worth often large thing however and it is preferable to choose quality. One can also see for that the substrate of culture advised on the individual record sheet of the species on the Web site and to prepare it is even.
- Sprinkle a little the substrate of each pot and to practise a rather deep cavity by means of a pen, of a piece of wood, etc, in which the radicular part of the small seedling will be placed. It is preferable not to sprinkle the pot too much so as to keep a little dry substrate around the hole to fill it later on when one transplants.
- Have at its disposal a ustensil of adequate watering, CAD which makes it possible to control the flow and the pressure of water. For that not need to invest in expensive tools, an ordinary plastic bottle whose screwed plug was pierced with one or more small holes is appropriate perfectly: it allows by pressure of the hand which holds it head in bottom to control at the same time the direction of the water jet and the versed quantity.
- once the pots of transplant and the ustensil of watering loans, one can then proceed to the transplant to be strictly accurate.

The transplant

It is advisable to make this operation with delicacy so as to as well as possible avoid breaking the roots, "to grip" the stem by holding it, in short of martyriser the plant at the time of its handling.
1 First of all separate the seedlings ones from the others, for that:
- If the substrate is dry and demolishes itself easily, one can make this dry operation, by raising the substrate by lower part at least of a flat object standard butter knife. Delicately separate then the plants ones from the others by holding them, following their size, between two fingers or by means of tweezers if the plants are small, or in simply raising them on the blade if they are too small and to store them for a few moments in position lying.
- If the substrate is compact and that the plants are likely to break at the time of handling, it is preferable to completely wet the substrate and to separate with the jet from water, delicately always, the plants by removing the ground to some extent.
Store for a few moments in position lying the seedlings before to have separated them.
2 Transplant one by seedlings in the individual holes applied to the surface of the pots which are intended to them:
For that hold the seedling between the fingers of a hand in the driving position with the top of the hole so that the radicular part is under surface and make fall ground with the jet from water practised with the bottle "water cart" or any other ustensil of watering adapted in the hole to fill it. Hold one moment the seedling after the stop of the payment, time that water goes down in the ground and that that Ci holds the plant.
3 times completed work, place the pots in a very luminous place, if possible the place where the seedlings will spend the next months. To avoid during a few days the full sun if the place chosen there is, envisage a piece of paperboard or any other screen so as to make shade and to gradually withdraw this screen in the following days.

After the transplant

In the days following the transplant, it is wise to give a small blow of inch to the plants for their "convalescence" by brumisant each day a little, which helps them not not to dry too much, while waiting for that their radicular system takes again strength and can pump water in the ground.
Not to brumizate too often, simply to avoid the draining of the substrate until noting the resumption of the growth.

Not to do, between others...

- One should not absolutely put fertilizer in the water of watering of the transplant, the risks of burn being then important.
- the water of watering should not be too cold, nor too heat. Ambient temperature of the substrate.
- Prevent packing the ground with the fingers if the plants are small.

Sowing very small or tiny seeds

One will place in this category seeds difficult or impossible to hold individually between two fingers, like seeds of cactus, of Kalenchoes, certain Crassulaceae for example.
Stages
One will not make soak seeds before sowing.
Once the filling of the container carried out, one will add a coarse pea grit or ballasting to it on which one will distribute in the most homogeneous possible way seeds.
Distribute seeds on the substrate a ustensil like a small spoon, a piece of paper in the shape of open horn or one limps of matches half-opened will make the deal.
Set out again then with stolen on surface seeds while tapping slightly on the ustensil containing seeds.
The seeds must for the majority "fall" into the interstices from the gravel or the large sand.
Slightly pack surface by means of a flat and dry object to which the seeds should not adhere, if not not to pack.
For humidification by capillarity of the substrate once sown seeds, prefer the steeping of the container in a basin by taking care that water level does not go up beyond the level of the substrate.
To let soak a few minutes at least so that the seeds absorb moisture.
Leave the container the basin of steeping and let it well drain before covering it and placing it in a hot place and at the shelter of the sun.
For the continuation, please take a look to the normal stages already approached for the other types of seeds.