Q.When To Plant Bulbs And Root Starts?
Lily of the valley roots, begonias bulbs and tricyrtis roots

Certified GKH Gardening Expert
Lily of the Valley will be best planted in Fall, as it needs a cooling period to grow. This article will help: https://www.gardeningknowhow.com/ornamental/bulbs/lily-of-the-valley/growing-lily-of-the-valley.htm
Trycertis should be planted in middle to late Spring, once the ground is workable. They won't mind a little frost. This article will help: https://www.gardeningknowhow.com/ornamental/bulbs/toad-lily/toad-lily-care.htm
The Begonia will be a tropical and will need to be planted when the ground warms up to about 65 degrees or so, though they will tolerate slightly colder temperatures. This article will help: https://www.gardeningknowhow.com/ornamental/flowers/begonia/tuberous-begonia-care.htm