You need to put them both in some container element and then apply the alignment on it.
For example:
.formfield * {_x000D_
vertical-align: middle;_x000D_
}
_x000D_
<p class="formfield">_x000D_
<label for="textarea">Label for textarea</label>_x000D_
<textarea id="textarea" rows="5">Textarea</textarea>_x000D_
</p>
_x000D_