Dear Ajacobson, Welcome. We have all toasted a plant in our garden careers. Nobody ever intends to do it, but it happens. The great thing about woody plants like your Viburnum is that they have a mechanism for handling stress–to drop their leaves to avoid any more inner moisture being lost, and try to save their underlying structure, the woody parts. So normally a woody plant that goes dry will shed like this, then resprout the next set of leaves. Now this doesn’t hold true for all woody plants. Many conifers (evergreens), for instance, have a harder time recovering after dropping needles. And if you really baked the plant totally, it may not recover–or some parts may and others will have to be pruned off. Do nothing right away except to keep it watered, and out of baking sun or other stressful situations. Don’t feed; an injured plant doesn’t want a boost of food. Let it get up and growing again first. And don’t assume what’s dead quite yet…give it some time to recover before trimming back anything. You may get lucky. M.