Can I change the old soil of potted bougenvellea ?
Thank you for your question. I think your plants are beautiful, and that you should follow the advice given in this (https://aggie-horticulture.tamu.edu/archives/parsons/publications/bougainvillea.html) Extension article:
"GROWING IN CONTAINERSPlants do best in large (5-10 gallon) clay containers if grown outdoors (clay containers tend to stay drier, thus stressing the plants) or in large handing baskets. The 10" basket is the commercial standard, but plants will do much better in 12" hanging baskets. Place the containers in full sun, or in a place where they will receive at least 1/2 day of full sun. If your bougainvillea is not blooming, it probably is not receiving enough sun or fertilizer. These plants thrive in the tropics in areas of low rainfall and intense sun and heat. Any well drained potting soil mix is suitable for growing Bougainvillea. Hatten's Nursery in Mobile, Alabama, world famous bougainvillea growers use a mix consisting of 4 parts of well rotted pine bark, 3 parts peat moss and 2 parts of coarse perlite. To about 5 gallons of this mix add 1/2 cup of Osmocote and 2 tablespoons of 19-5-9 slow release lawn fertilizer."