Adding pine needles to compost is ok. They do take longer to break down and will cause in increase in acidity in the compost which is ok for acid loving plants. If you do not desire acid compost be sure to sprinkle a layer of limestone over the pile and to turn it in.

I never heard that idea, but it makes good mulch, especially for acid loving plants. A layer on top would retain moisture.

Loosestrife, I think Novicetony means potting compost to use in hanging baskets, not composting.

And no, I wouldn't bother, I can't imagine why anyone would think pine needles would hold water unless they were being used as an acidic mulch layer on top. Mixing them in your potting compost will also make it very uncomfortable to handle. Buy water retaining gel or crystals, or add perlite or vermiculite, or just use ordinary compost and water frequently.

thank you i take you advice not the friends advice,,,