A certain increase in growth can be achieved by keeping plants in the right conditions. This means fertilizer, temperature, water, etc.
There are also a few things that might increase this further, for example Hydrogen sulfide:
http://www.sciencedaily.com/releases/2013/04/130417185531.htm
However none of these offer "magical" increases and introducing a simple substance will never be able to do that.
In order to grow plants need to pull up nutrients from the surface, process sunlight and water. Cells need to reproduce and arrange themselves correctly, etc etc.
Plants can grow very fast (see bamboo for example) but there are trade offs for doing so. Note that hardwood like oak for example grows much more slowly than pine.
So in other words, yes if you mean a small increase. No if you mean "magical" trees shooting up into the air.