Most people tend to be afraid of elemental sulfur, but they shouldn't be. It is one of the best methods of acidifying the soil, yet it is surprisingly gentle and is usually considered to be an organic gardening practice. I buy it in 20 pound bags on Amazon. Yes, you should use pine mulch, compost and similar things, when available. You should also try to amend you soil to try to get a sandy loam. However, once you have done all of that, you probably will STILL need to acidify the soil more. But also keep in mind that your soil will CONSTANTLY be trying to gradually revert to its normal pH. Blueberries like a pH of 4.0 to 5.5 or so. This is definitely an acidic soil level and is very close to the acid level of apple cider vinegar. Meanwhile, most people have neutral soil, in the range of 7.0 to 7.5, and, if you live near mountains/hills or lakes/rivers that contain limestone, your pH for both soil and water will probably run in the range of 8.0 to 8.4. Blueberries might possibly barely survive, but will never do well in such soil. So, you must acidify it. ONE POUND of yellow, elemental sulfur powder mixed into the surface inches of 100 square feet, will drop the pH by 1.0 points over a period of about a 1 year. It works because the action of soil bacteria, along with moisture and warm temperatures, allows the soil bacteria to gradually convert the elemental sulfur to sulfuric acid, and this acid is never really free, but it neutralizes the limestone and alkaline components. So, 4 pounds of sulfur in an area of 10 x 10 will often drop the pH from 8.0 to 4.0 in a year or so. But the soil, and water, will push back, especially if the soil is derived from a moderate amount of limestone. The limestone contained in the soil continues to dissolve and will work to bring the pH right back up. Around here, we need to use 5 to 10 pounds of elemental sulfur in such an area, in order to get the pH down to an adequate level. In addition to the above mixture of sulfur with surface soil, if you soil is on the alkaline side, like ours, mix TWO whole cups (1 pound) of sulfur with the dirt in the planting hole, at the same time as you plant the blueberries. Please note that these instructions are for using ELEMENTAL SULFUR, which is generally a bright yellow powder, AND, it takes time to work (a year or more), AND you need to keep reapplying sulfur to the top of the soil at a rate of 1/2 pound to 1 pound per 100 square feet, every year or two. I also went online and bought some simple electronic pH testers for around $20 or $25 dollars each. When I want to test my soil, I mix some soil with DISTILLED water (available at most grocery stores) and use the tester on the resultant runny mud mixture.

What fruitnut suggests has worked very well for me. I first acidified my potting soil (1/2 peat compost and 1/2 azaella, camellia mix) with about 1/2 cup of soil sulfer (large pots). I then planted, taking care to break up the root ball (apparently very important, as they can have root ball shock if you dont' do this). I watered in carefully, then set my drips. I checked the pH for the next couple of weeks every day. I had to adjust my pH down a wee bit, and I did this with a few tablespoons of ammonium sulfate diluted in a couple of gallons of water. I made sure the pH of the acidified water was about 4, since I needed to pull down the pH a bit. That did the trick and they have been doing extremely well ever since. I did check the pH about 3 or 4 weeks ago, and it was still around 4.5 to 5.0 per pot. So, they're happy campers and I'll even get some fruit this year. After the fruit is off, I'll pinch back like what fruitnut has done to keep the tallness down, and get them to bush out a bit, especially my more leggy blueberries. Patty S.

I'm new to blueberries this year as well and mine are doing the leafy color change as well, the same as you show in the last pic. I'm in a heavy clay/alkaline soil area also, so I amended my soil with ammonium sulfate to instantly lower the PH as well as mixed in sulfur for it to take the 6 months or so it does to further work into the soil to help maintain acidity. The local soil is present along with thoroughbred compost and topsoil mix. I finished off my beds with pine bark mulch which is also said to be on the acidic side (ya gotta do everything ya can in a limestone region). I water my blueberry plants using ONLY rain water that I connect from the gutters on my house in the disappointedly few times it has rained all spring. The last 'good' rain lasted 25 minutes, but I filled over a dozen 4-gallon kitty litter containers, put on their lids and store under my back deck for everyday use. I noticed the leaves tend to crimp at the ends in a yellow-green area while the more mature leaves do the reddish border. I've witnessed these conditions periodically go away and come back. I suspect it may have to do with the amount of water I give to each plant because when it does rain (seemingly rarely, as it seems to miss my area relentlessly), the fresh rainwater will perk up the plants and the colors will go to a darker green (at least for awhile). As it tends to get dryer out, the newer leaves curl and the older ones get the red borders again. See if you notice the same pattern..

Blueberries like rich, well-drained soil that is acidic. If you treat them like a rhododendron, the usually do well. Oak bark mulch, pine straw, peat moss,composted horse manure...I have used all of these at one time or another. Iron and sulfur can also be used around blueberries in the cool wet seasons. They like the iron and the sulfur acidifies the soil. A good layer of mulch on top of the soil is helpful with water retention in the root area. Just do NOT pile mulch up around the base of the trunk(s). IF you have to grow it in a pot, recognize that the roots will be hotter (and no doubt dryer) than they would prefer to be. Pots dry out quickly. Do NOT set the pot on a sunny patio (it will bake). Pots also freeze and thaw easily which will cause winter damage as the plant will often start budding on a warm winter day if left outside in the pot. Then WHAM, back to winter. Best to put the entire pot into the ground for the winter if you MUST leave it in the pot. All things being equal, it'd be best to plant it somewhere...