Hi, I have recently bought a dehumidifier for my flat and wonder can I use the water from it to water my pot plants and things like blueberries plus my iron.
I don't see why not. Your dehumidifier is just a cooling device which causes the moisture in the atmosphere to condense and become water. I wouldn't leave it in the tank too long because any water lying about will become manky. Should be fine if it's fresh.
Yes, the water will contain no dissolved substances and be neutral in pH. It is effectively the same as distilled water.
I use a dehumidifier in my conservatory through the winter and constantly recycle the water, as you can imagine, I have hundreds of plants, seedling etc they make a lot of moisture so every day the chamber is emptied back into the watering can.
Yes, it will be like using rainwater so great for the blueberries if your tap water has lots of calcium in it. Great for irons as it won't cause limescale to build up.
My mum uses hers to water her orchids.