Pinching Eucalyptus and Wild Bergamot?

I am growing the above plants from seed purchased from you. The Eucalyptus now has four pairs of leaves and the Wild Bergamot three pairs. How do I care for these plants? Is it necessary to pinch the leaves so they produce strong stems?

If the plants appear to become thin stemmed, the fault would be not enough light. It makes the plant stretch- hoping to get to more light. Gradually increase the light to avoid burning the foliage.
The eucalyptus could be pinched if you wish it to produce branches or wish to keep it within bounds.
The wild bergamot should not as a rule be pinched until it had developed several stems and then you could nip off the tops to get tea makings. It may stop flowering if done too close to blooming time.