Q.Is begonia flower size determined by species or an additive with fertilizer?
I live in Redding, CA where the temperature can stay over 110 for days. I plant my tubers in pots with potting soil that has fertilizer. They are in a shaded, screened-in patio. They receive little to no sunlight. I water with a drip mist system every three days-every other day when the temp. gets above 100. The leaves are always large, but the flowers are disappointing. Are the flower size determined by species, or is there something I can add to the fertilizer that increases the size and amount of the flowers. Thank you for any suggestions.
Certified GKH Gardening Expert
This is, mostly, determined by genetics but environment can have an impact. Usually you can help the bloom process by adding phosphorus and potassium, or fertilizers high in these and low to no nitrogen. This will usually help with the blooming. Also, try moving them where they will get a little bit of sunshine, dappled shade or morning sun.
This collection of articles will give you tips on the care of begonia: https://www.gardeningknowhow.com/ornamental/flowers/begonia
https://www.gardeningknowhow.com/ornamental/flowers/begonia/tuberous-begonia-care.htm