How much to fertilize, when to and what type of adenium fertilizer should you use? There has been plenty written about how to fertilize your desert rose plants and what mixture. There is no one correct single answer. Some people say to use low nitrogen all the time for adenium others use 20-20-20 or miracle grow with good results. However, the answer is a question: What is your current desert rose plant growth cycle and what is the age?. Is it a mature plant 5yrs plus? Seedlings? or a young 2..4 year old plant? Depending upon the stage of development and the amount of water the plant received will determine what you should use to growing your adenium plant.
Presently, we use a 13-13-13 time released fertilizer for our desert rose plants that are 3+ years old. This gives them enough fertilizer to promote growth and enough nitrogen (not a lot) for strong flowers buds. The only liquid we use is to supply micro-nutrients twice a year for the adenium hybrids. Adeniums are not true desert plants. Yes, they are succulents, however, they like frequent water! They are more tropical in their growing patterns. If we stay with low nitrogen fertilizer all the time the flowers are buds and flowers are not as good.
We do not fertilize at all until the desert rose plants are 1 year old with a cuadex of 3/4″ or more. At that time we use a 6-6-10 (low nitrogen) time released fertilizer what is not easy to get to help prevent elongation of the adenium plant trunk and grow fatter roots. yes, we do others things to make the adenium roots fatter (cropping, plenty or water,etc.)
Why do we use time released for the desert roses? Time released fertilizer does not shock the plants, it gives us more relief from frequent adenium care and out plants get tons of water here in south Florida so liquid fertilizer gets wasted out too fast!
One more thing , we do dip our plants roots in a hormone super thrive for 30 minutes when re-potting. The nutrients and micro-minerals in superthrive really give the plant a boos. On adenium plants received from Thailand (95% leafless bare root plants) the superthrive seems to make the plants burst out with leaves fast in a couple of days