First of all in a perfect would I would like to keep her entire till 18 months, the reason for this is not to hinder her growing etc I am NOT planning on breeding my dog at all. But I do have some factors that concern me with keeping her entire till then as there is an entire german shepherd mix dog on the farm he is normally tied up most of the day & off when they are away, but in saying that when my dogs are off they can get to where he is tied up. She is actually scared of him & I like this so I haven't introduced them. And sometimes on the weekends they do see each other, but when she is older I would just put her away.
As far as I am aware correct me if I am wrong, I am fairly safe in her not menstrating till she is 8 months or so. So I am assuming I can safely leave her spaying till about then at the very least. But any ho enough of my rambling please tell me what you think of the situation & how long I can safely leave her & what would you recommend. I am confused & just want to right by my dog & her growing etc