Buddleia shrubs are a favourite of local insects, butterflies being the most obvious when summer comes. They also grow easily and where there is one bush you’re likely to find many tiny offspring in pavement edges and plant pots. But the plant is apparently not edible or medicinally useful , a pity! It can be used to produce natural plant dyes. I’ve read some reports that rather than helping insects our even being particularly attractive to them, Buddleia may take over space from really beneficial plants. I’m not too sure about that as I recall many days, standing close to the plant and counting the butterflies on it. They appear to love it.
Another of my favourites is the humble Pansy. It can be used interchangeably with the herb Violet.