Raspberry bushes typically thrive when given plenty of nitrogen, phosphorus, and potassium. For this reason, you may want to look for a raspberry fertilizer that contains equal amounts of these ingredients. The product should also contain traces of other minerals, and some of these ought to be in higher quantities than others are. Where you are growing these plants can play a part in the type of fertilizer you choose. It is very important to add the right amount of fertilizer and to do so at regular intervals.
There is usually a set of three numbers listed on a bag of raspberry fertilizer. This represents the amount of nitrogen, phosphorus, and potassium included in each mix. These three nutrients help enrich the soil, thereby contributing to the plant's overall health. Since they are all equally important ingredients, a good fertilizer will contain the same amount of each ingredient. A 10-10-10 variety is a common type of fertilizer that can be ideal for raspberry bushes.
Other nutrients are also helpful in raspberry fertilizer, but in smaller amounts than phosphorus, nitrogen, and potassium. These ingredients are typically listed on the bag in their order of concentration. There should be higher concentrations of copper and iron than zinc and sulfur. Raspberry fertilizer could contain even smaller amounts of calcium and magnesium; however, these minerals may not be needed if you have recently added lime to the soil.
When creating rows of plants, you may want to choose a granulated raspberry fertilizer. This type can be easy to sprinkle by hand or with a commercial spreader, which can be convenient when fertilizing several plants at one time. While granulated fertilizer could still be used for container fruit, this product might be better if used in stick form. This is because it can be easier to place a fertilizer stick in a container than it would be to spread granulated fertilizer there.
You can purchase raspberry fertilizer in different sizes, and the one you choose can depend on how many bushes you are caring for. Most gardeners like to use around 1 pound (0.5 kg) of fertilizer for every 100 feet (30.5 m) of ground space. If fertilizer sticks are used instead, only one stick per container is usually needed. Rows of raspberry bushes typically need to be fertilized twice a year, once in the spring and again in fall. Containers should have one fertilizer stick added approximately every eight weeks, in most cases.