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i have some rose plant on my roof most of those are in pot. size would be around 10-12 inches, i have started using DAP fertilizer in my pot about 1 table spoon per plant but still no visible impact on my rose plant although i have applied only 1 time,i am also using liquid rotten oil cake 2 times in a month, and indifil-m-45 for fungus attack. but i think still a have something lack as my plant is not exposing like any rose plants of nursery. please give me some suggestion to make my rose plants beautiful with big leaf and tall bushes and big flower.