Q.Begonia care
I started a Begonia from cuttings. Plant looks healthy but drops its healthy looking leaves before they are 2 to 3 inches long. What brand of fertilizer do you recommend? Is temperature my problem?
Make sure the rooting mix is light and airy so that the roots can form.
The cuttings should stay evenly moist but not soggy.
When the cuttings have taken root and began to form new leaves you can fertilize with a all purpose fertilizer--at half strength.
Reapply after 2 weeks on more growth at regular strength.
https://www.gardeningknowhow.com/ornamental/flowers/begonia/begonia-propagation.htm