I’ve often noticed that snowdrops flower earlier in drier ground. They spread better where it’s damp, but there is little doubt that the extra warmth of ground dried out by, in particular, the roots of trees and shrubs encourages their flowering. We had little bouquets fully open at the foot of cypresses (which have mats of roots concentrated close to their trunks) while the squadrons scattered on the long grass were just showing their heads.
The same thing doesn’t quite seem to apply to winter aconites. I planted them close in to a mature beech where the tree roots are densest. They flowered, but sparsely. Each year, though, their seedlings form a wider circle round the tree, growing better and flowering earlier as they reach what is presumably less rooty ground. Or is it? Are the most active roots in reality under the edge of the canopy? Do aconites agree with snowdrops?