Hello Julia!

Great of you to grow blueberries; I've started with them myself. I'm not familiar with MKP and not sure what the directions of your micronutrient bag advise, but as for the Ammonium Sulfate: There is a grower on here named Fruitnut who has been extremely successful with growing blueberries (in containers) and he uses a rate of 1 tablespoon per 2.5 gal of water once a week. He also added Osmocote slow-release. I'll link one of his blueberry posts for you to read through. Some great info there as well as fertilizer recommendations.

Happy Growing!

Dan

Here is a link that might be useful: One and 7 yr blueberry growth with pictures

@BahamaDan,
I guess my mistake was to apply 1 tablespoon per 2.5 gal of water almost EVERY DAY! I didn't know that it should be applied only once a week. Thanks for the information, now I can do it the right way! =)

No problem Julia, happens to the best of us. I've killed my share of plants when I was starting out as well; the important thing is you're willing to learn how to better cultivate plants and it is that attitude and willing disposition that will lead you to success with your plants!

A good method when container gardening is also to flush your soil with straight (unfertigated) water every 3rd or 4th watering, so as to prevent salt buildup. Not sure if your blueberries are in containers; if not disregard :)

@BahamaDan Yes, they are in containers!
Last year I bought them and started fertigating every day with ammonium sulfate and water. They grew very fast and strong. They were all beautiful!!! But then suddenly, one day, they began to burn.... That's when they stopped growing at all... It was as if they had got into dormancy, except it was not winter.... I had to wait many months for them to recover... Now they finally started to grow back again. Don't wanna repeat the same mistake.

One thing I noticed is that the Jewel variety is less prone to burning than the Snowchasers. My Snowchaser blueberries got all burned from the fertilizer, while the Jewels remained mostly green and healthy, with only a few leaves burned.

How are they doing now Julia? ;-]

Here's a picture of my Sunshine Blue, I really should fertilize it more though as I honestly can't remember the last time I gave it liquid feed lol. Hopefully I put some granular acidic feed on the soil surface a month or two ago...