thats not all true cus i use 10-54-10 schults bloombuilder for flowering and fruiting plants and my plant is doing just fine just make sure it dosent say on the container that its for roses ONLY and ull be ok just make sure u give plain water between nute feedings.but 3 weeks is alittle early inless u want a smaller plant cus when u put it into flower it wont put 100% into groth it will only put about 15%into groth and 85%into flowering