Everybody who begins to sow has many different questions about all steps of the cactus germinating process. 5 sowers from russian site www.iplants.ru answered to FAQ about cactuses germination. These are: Anjuta, Pola, Stivi, Severina, irina-bahus. I compiled their answers to find common rules and show that there are many variants of sowing. Everybody can choose convenient and available ones for himself.
Sowing
Pots
You should take shallow pots (height 2-5 cm).
Soil
Prepare loose and poor soil. It must consist of small fractions (1-2 mm) and be as sterile as possible, because cacti germinate in habitat after the dry season and they have no immunity to infections and viruses. The soil may contain different elements: sand, peat, mineral substrate, zeolite etc.
Soak
Soak before sowing accelerates germination. Soak helps sterilisation of seeds if you'll ad manganese crystals to water. But it's not necessary. Slow-germinating seeds will germinate slowly in any case, and manganese crystals may be added during watering.
Temperature
In most cases temperature must be above 20 °C and you should provide a difference between the day- and night-temperature (imitate it's habitat). Desired day temperature are 24-30 °C. The higher the temperature the less the probability of appearance of bacteria.
Light
Seedlings in habitat grow in the shade of big cacti and other plants, so they don't need much light during germination and for the first month after germination. Later it depends on the conditions of your seedlings: strong green ones don't need additional light. Remember, most seedlings have an elongated in the first months after germination. They stretch to the sun in habitat, so you should adjust them to the sun little by little.
Humidity
Humidity must be high before germination and in the first month of seedling growth. After this period you should decrease humidity little by little. It's necessary to keep a close watch on your cactus seedlings all the time.
Ventilation
After germination your seedlings should get used to lower humidity. Slowly increase ventilation. Usually we ventilate when we check our germinating seeds.
Cactus seedlings (shoots)
Temperature
As a rule temperature conditions don't change (must be the same as during
sowing).
Light
We give additional light at dark time of year (in autumn, winter and spring).
Humidity and ventilation
You should decrease humidity and increase ventilation to train
seedlings to normal life little by little.
First repotting
Frequent repottings stimulate growing of roots, but you can lose many seedlings after first repotting, so you can grow them in your shallow pot for a long time (especially if you have few shoots). Besides it's well known that cactuses seedlings like to grow «in crowd». The main reason for repotting is appearance of bacteries, infections and Cyanobacteria (blue-green algae) («blue-green luck» in russian). This «luck» will appear in
any case, early or a bit later. Cyanobacteries spread very quickly and form black layer covering the seedlings, so air can't get to the roots. The second reason is when seedlings begin to crowd and disturb each other.
First repotting
Soil
The soil must be a bit coarse (for roots growing) and a little richer.
Planting
Don't work cactuses deeper into soil. Put them into little hollow and add a sand.
Soil humidity and watering
Cactus in this age has very few roots, and some of them always will be damaged during repotting. Seedling will not be able to drink normally. If the soil will be moist («bog»), the cactus will rot, so you should use slightly damp (almost dry) ground (the hollow must keep form). Don't hurry to water after repotting.
light and ventilation
Usually ventilation is not needed, because most seedlings have already been trained to usual conditions. Additional light is necessary only at dark time of year. Remember: the young seedlings live in the shadow of big plants in habitat, so you should avoid a direct light. It's better to screen them with white paper at the south windows. When sunlight is excessive, the seedlings become slightly red and grow slowly. There were many
cases of burns, you can lose seedlings with big burns.
Conclusion
There is not one pill for all diseases, and there is not only one exact rule for growing cacti. Cacti like people are different, so you should carefully look after your seedlings: some cactuses will wither if you'll forget to water, some will stand in dry soil, but some will rot from moist soil. Some will become red on the windowsill, and it means this specie doesn't like much light. Some will become long and thin – you can understand this specie needs much light. Study habitat conditions for species you sow: ones from hot deserts need high temperature and sun, ones from highland habitat don't need high temperature, but need much sun and good ventilation.
Watch everything about your seedlings. Some of them will forgive us our mistakes, but some will die for any reason. Remember: you will lose some seedlings in any cases. But if you will be attentive and careful, you can grow cacti from seeds almost without losses.
Credits
This article was originally published at http://iplants.ru/cactus-seeds.htm with many thanks to Irina Bagdasarova for sending us her translated article.
