Growing Living Stones at 63rd Parallel North

during october i water and fertilize my living stones every 10 days: on the 6th, the 16th and on the 26th. at the beginning of the month i still find webbing on the monilaria plants so i also spray with the diy miticide on the 6th and on the 16th. i reduce the daylight hours gradually untill the plant lamps are on only 12 hours a day. i am aiming at 8 hours at winter solstice and at 16 hours at summer solstice but i began to wonder if one is too little and the other too much. i read about the 34th parallel south (about the parallel of cape town) because i believe that the southern tip of africa has the most extreme light levels the living stones could possibly encounter in their habitat. well, their habitat is actually a bit more north from there in the namib desert but i think it's close enough for an approximation of the most extreme light levels. at the 34th parallel south the sun is visible for 14 hours, 28 minutes during the summer solstice (in december) and 9 hours, 50 ...

this month i continued gradually lenghtening the photoperiod (daylenght) with my plant lamps. at the end of the month i had my plant lamps on for 12 h/day. during this month i discovered that the monilaria plants were beginning to grow very strongly towards the light source and that one of the argyroderma plants had also begun changing its leaves the second time. i bottom watered and fertilized my living stones on the 6th, the 16th (one conophytum plant was wrinkled), the 22nd and on the 29th of march. a new monilaria leaf tip turned bright red after bursting into light.

this month i discovered that the 2 lithops plants with brand new leaves had etiolated. it means they had received too little light (8 h/day) and i began gradually lenghtening the photoperiod (daylenght) with my plant lamps. at the end of the month i had my plant lamps on for 10 h/day. i bottom watered and fertilized my living stones on the 2nd, the 7th (i didn't fertilize), the 11th, the 17th, the 22nd and on the 28th of february. the 2 etiolated lithops plants on the 7th of february the last lithops plant is finally splitting

as stated in the description of my blog i live at the 63rd parallel north and the sun is visible here "for 20 hours, 19 minutes during the summer solstice and 4 hours, 43 minutes during the winter solstice". wikipedia i live in a  temperate climate , in a  subarctic climate to be exact although we don't experience permafrost here. the winter temperatures are generally subzero (degrees celsius) and the summer temperatures at least over + 10 °C. however i am growing my plants indoors and the temperature is therefore at least + 20 °C all year round. i don't know how humid it is in our apartment but during summer time my laundry takes longer to dry and the doors seem tight in their frames. during winter time the central heating keeps the indoor air very dry. e.g. the need for more moisturizing skin care products is evident during winter time. my growing conditions affect a lot what plants i grow and what equipment i need for growing them.