My chives are simply thriving but they are starting to become crowded. I have 5 large bunches that should be seperateable. Is it important to seperate them and replant them in richer soil? When is the best time to seperate them? Now? Fall or does it really matter? Should I break apart the large custers or simply seperate the large clusters from each other and replant? Do I even need to worry about it? Instead of replanting can I just add some compost and fertlizer to the soil they are in working it as deep as I can and leave them alone otherwise?