When you purchase rhubarb plants or roots the bigger the plants or roots the earlier you will begin to enjoy the fruits of your labor. If you purchase a two gallon plant you should begin to harvest a few spears even next year. If you purchase a 4 inch plant you probably should wait three years.
I like the deep red stalks like Canada Red. It just look better in the garden.
Rhubarb likes a rich organic soil. Many folks every year put a bag of compost or cow manure a few inches thick going out about two feet or so from the base of each plant.
When you plant Rhubarb mix about 10% compost or bagged cow manure back with the top soil. The hole should be about twice as wide as the root ball but no deeper. More compost is not better. You do not want to change the soil structure around the plant or it will have a hard time sending roots out into the soil away from the hole you just dug.
One ingredient that Rhubarb responds to is mycorrhiza. This root-fungal complex greatly increases the plants ability to take up nutrients. It attaches itself to the root hairs of the plant and lives on plant exudates from the root but then helps the root absorb nutrients from the soil. One of the trade names for this product is Myke’s. This product is so good it usually comes with a three year warranty on the plant.