Nutrients in cottonseed meal are more readily available to plants in warm soils, and there is little danger of burn. Cottonseed meal is frequently used for fertilizing acid loving plants such as azaleas and gardenias. Blood meal is dried, powdered blood collected from cattle slaughter houses. The gardener must be careful not to exceed the recommended amount suggested on the label. In addition to nitrogen, blood meal supplies some of the essential trace elements, including iron.
Fish emulsion is a partially decomposed blend of finely pulverized fish.
No matter how little is used, the odor is intense, but it dissipates within a day or two. Fish emulsion is high in nitrogen and is a source of several trace elements. In late spring, when garden plants have sprouted, an application of fish emulsion followed by a deep watering will boost the plants' early growth spurt. Contrary to popular belief, too strong a solution of fish emulsion can cause plants to burn, particularly containerized plants. Manure is a complete fertilizer, but low in nutrients.