How to Grow San Pedro Cactus from Seed
First, make sure you have the following supplies or similar.
For your container:
– Plastic box with a tap or a drain
For your soil mix:
– Potting soil (50%)
– Fine sand (20%)
– Pebble stones (20%)
– Perlite (10%)
– San Pedro Seeds (Trichocereus Pachanoi) or similar
Make small holes in the bottom of the box in which you are going to grow the cacti, so an excess of water can run away. Because too much water can let the roots of the cactus rot away.
First divide the pebble stones in two, and spread one part on the bottom of the box so it’s completely covered. The next step is mixing the potting soil, sand, perlite and the other half of the pebble stone. It is a good idea to sterilize the mixture before using it, because it is possible that batteries live in it that can obstruct the growth process. To do this, put the mixture in an oven proof bowl and heat it during one hour at 80-100 °C, or during 30 minutes in a microwave on a low setting.
Once you mixed it you can make it wet. Keep a small portion of the mixture apart, and add water to the rest. A good way to see if the mixture is wet enough, is to squeeze it. If it’s not possible to squeeze out the water, then it’s perfect. If water still comes out, then add some more soil. Once the soil has the right rate of humidity, you can fill the seed box.
Sowing your seeds
We can now push the seeds into the ground with a pencil. About one-and-half to two-times the height of the seed is perfect. Spray the soil a couple of times with water and put the tap on the box.
The best temperature to let the San Pedro seeds germinate is in between 20 and 30 °C, preferably 23 °C. To reach that temperature you can put the seed box close to a heating system or by the use of an electric blanket. But don’t put the seed box directly on the heating system that could dry out and will prevent the seeds from germinating.
Some people use a heating element for a terrarium or aquarium to reach the perfect temperature. Of course, this is not necessary, yet it can help to speed up the germination process.
Maintaining Humidity Levels
It is best to keep to humidity level high during the germination phase of the San Pedro. So the bottom must be kept humid. After a while, the cacti will grow enough to be able to adjust to a very dry environment. To have the cacti getting used to the dry circumstances, we make some holes in the tap of the seed box. After a couple of weeks you can remove the tap permanently, though you have to keep the soil humid for another two months.
When the San Pedro seeds germinate it is important that the seed box is not put in direct sunlight. Use fluorescent light or an energy saving light bulb, during 16 to 18 hours a day. When the cacti are a bit stronger and older (2-3 months) you can let them get used to indirect sunlight. When they are about 1 year old, they can be put in direct sunlight.
After this we treat them as adult specimens and give them less and less water. Make sure to let the bottom dry up completely before watering them again, to stimulate dry growth conditions.
When you cacti is about 1 year old (or has a diameter of 1 centimeter), you can repot them. Keep in mind that a bigger pot is not automatically better. Try to get a pot that is about 3 to 4 times its width and 4 to 5 times the height of the cactus. The repotting gives you the opportunity to provide more nutrients to your cactus. Providing the San Pedro with a deep pot helps the cactus to develop a healthy rhizome.
Taking care of your San Pedro Cacti
San Pedro CactusCacti are used to dry circumstances and that’s why you don’t need to water them a lot. The best period to water them is from spring till autumn. When the summer is very hot, you need to water them a bit more.
Never water them too much in the winter, especially when they grow outside, because the combination of coldness and humidity will damage the San Pedro. Only give them very little water very occasionally to prevent the cactus will dry out completely.
San Pedro cacti especially grow from spring till autumn. Especially in this period they need water and nutrients. Use special cacti nutrition and make sure you never give them too much of it. Good nutrition for cacti always contain a low level of nitrogen and a high quantity of potassium and phosphor. These substances are indicated on the label of the bottle in a NPK value. A good NPK value for cacti is 4-7-7 or even 2-7-7.
A good way to water the San Pedro is to place the small pots a couple of minutes in a sink with a small layer of water. This way of watering makes sure the roots will develop well because they need to grow downwards to take up the water. Even though this is a good way to water them, you can also water them from above, from time to time.
In the winter the cactus has a preference for an environment of 5-10 °C. Room temperature is also allowed, though colder is better. Make sure they get enough light.
We hope you enjoy growing your own San Pedro cactus. It is one of the fastest growing cacti in the world. Under the right circumstances, they can grow half a meter a year.
If you want to know more about growing cacti, there are several interesting books available:
– Cultivation and propagation of cacti, by Trout
– Peyote and other psychoactive cacti, by Adam Gottlieb
– The Peyote Book, by Guy Mount