I planted spinach for the first time and it has done well.  When I pick it I usually just pluck the leaf/stem off and let the stalk remain in tact.  Well, now the stalks have gotten so tall and out of control.  They still have leaves on them but now I am wondering when I first started to pick them should I just pull them up from the ground instead? 

I have noticed this happens with certain kinds of my lettuce too.  I thought the right thing to do was to pluck the leaves and lieave ths talk.  Now I am not so sure.

Any thoughts or suggestions?