Label the canisters with the name of the pollen parent. Do not put a lid on the canister so they will dry out and not get moldy. After a few hours (on some rose varieties), or the next day (on other varieties), the pollen sacs will burst open, thereby releasing the pollen. Sometimes you will need to shake the canister so that the rose pollen will release from the pollen sacs. The black film canisters make it easy for you to see the pollen, which looks like a fine yellow powder. The pollen will stay fresh for about two weeks.
Fertilizer: Roses are heavy feeders, and will benefit from a steady supply of nitrogen, phosphorus and potassium. You can provide these nutrients with either liquid or granular fertilizers, at a ratio of approximately 5-8-5. In most cases, regular applications of compost, rotted manure, fish emulsion and seaweed extracts will provide roses with all the nutrients they need. These organic amendments also help to moderate pH imbalances and stimulate beneficial soil life. Other organic amendments favored by rose growers include greensand, black rock phosphate and alfalfa meal.