There's no difference - simply two ways to describe the mineral elements growers use to enhance plant growth.
As a beginner grower the most important thing to know is the difference between "plant food" and "plant fertilizer (or nutirents)". The real food plants use for growth are light, water, and air. If you don't get those right your choice of fertilizer (nutrients) won't matter.
Having said that, the best choice of nutrients would be Dyna-Gro's "Orchid-Pro 7-9-6". It's an excellent formula that has everything your plants need for healthy growth and dramatic blooms. And it's easy to use - simply add 1/2 tsp. to a gallon of water and use it on all your plants - blooming or not.
"Grow formulas" are blended for the growing season (high in nitrogen) when the plant is building up the energy to bloom. "Bloom formulas" are adjusted for the blooming season (low nitrogen and high phosphorus) to enhance flowering. Many growers like switching nutrients to get the best of both worlds.
All fertilizers contain three main ingredients (called macro-nutrients), Nitrogen(N), Phosphorus(P), and Potash(K). The three numbers on the front panel describe what percentage of each element is in the fertilizer. This is called the "NPK" ratio.
Orchid-Pro is an excellent "middle of the road" fertilizer that can be used during both growing and blooming seasons. Simply add 1/2 tsp of Orchid-Pro to a gallon of water and apply as needed - whether your plants are blooming or not. Save whatever you don't use for next time.
It's always a good idea to keep your nutrient supply fresh. We recommend using all nutrients in a year or less. The chemical elements inside the package are in a concentrated form and they deterirate over time.
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