The method I use on our blueberry shrubs is to mix one tablespoon of water soluble fertilizer with 4 gallons of tap water, and spread this around the base of the shrub. This is done once a month, in March, April, May, and June. I am using Schultz Plant Food-acidic formula, but in past years I have used Miracle Gro-acidic formula. This is a minimal amount of fertilizer, but the plants do well. We live near Lake Monona, here in Madison, Wisconsin, and I do not want any excess fertilizer to run-off and get into the lake.

Hello TGibson, Sulfite,is that Sulfur?If it is Sulfur,a yellowish powder or granule,it can be put on about once a year,about a couple tablespoons per plant,mixed gently into the soil surface.It may take about that long to see results though,as the microbes change it to Sulfuric acid. It is a good idea to see what the actual soil pH is,by way of a soil test or an accurate meter. It will probably make a difference to pull the berries off the first couple of years,so that the plant can grow more in roots and leaves.Not so much fun on our part. Bumblebees are usually the most common pollinators of Blueberries and they will fly a good distance between plants. Strawberries also like an acid soil.I'm not sure about Raspberries. I also have a Pink Lemonade Blueberry plant,that I picked up early this Spring and it is growing like a weed.It only has a few berries though,which I'm eager to try. What is your soil amended with?I use Pine bark mulch and Moss Peat.About 70/30 mix. I'm going to close with the words that the man who welcomed me on this forum a little over a year ago, when I announced my intentions to grow them."Blueberries are the easiest things to grow until their not".Have fun and I hope they do really well. Brady

The big three soil nutrients found in fertilizer are nitrogen, phosphorous, and potassium. It doesn't matter if you are growing corn, peanuts, or blueberries, its the same big three. There are some other nutrients that plants need, but these are a small percentage of the total. You can pick up some Miracle-Grow and read the label, to learn more about fertilizer. Changing soil pH is not the same as adding fertilizer. Blueberries need the soil pH to be somewhere between 4.5 and 6.5, or they will not take up the nutrient that they need to grow. There are several ways to lower soil pH. Usually, granulated sulfur, aka agricultural sulfur, is mixed in with the soil before the shrub is planted. So, you have to dig out the hole, put back some of the dirt, and mix sulfur with it. Then you put the shrub in, and finish the process. Another way to lower soil pH is to mix a small, measured amount of acid with irrigation water, and put this on the ground around the shrub. For instance, I add 4 fluid ounces of white vinegar, 5% strength, from the grocery store, to every 4 gallons of tap water. We have hard water, our tap water contains dissolved limestone. The vinegar lowers the pH to around 6. However, the vinegar is consumed by soil bacteria, so the beneficial effect only lasts a month or so. The reason for testing the soil, for pH, is to keep the additions of sulfur and other additives within an appropriate range. Too much sulfur, or too much vinegar, will kill the shrub.

I've also bought soil fertilizer for container blueberry plants. You can not use it as directed. You have to dissolve it in water and measure the ppm or ec. Two ways of measuring the same thing. I follow standard ppm levels for feeding heavy then only using water for 2 or 3 waterings. You could do that or use the standard ppm levels for constant feeding. Be warned there are 2 ppm scales and they are not interchangeable. Also some soil fertilizer if not all are time delay aka won't dissolve. You have to crush it to dust or use a blender.