In lots of ways I think of this as the native Daphne. Small, difficult, subtle, and then there is this show stopping fragrance that knocks you over and you WANT one.
The boronia with the best fragrance is Boronia megastigma known as Brown Boronia. This should be the floral emblem for the Hawthorn Football Club, with dark brown petals on the outside contrasting with bright yellow on the inside. Every organ of the flower has scented oil glands (the source of the essential oils for the perfume trade) and the fragrance is superb. There are numerous cultivars of this Boronia, all have pretty flowers and a lovely scent, look for ‘Heaven Scent’; ‘Jack Macguire’s Red’ and ‘Harlequin’.
Boronia megastigma lutea is a pure yellow version with an equally strong, if not stronger, fragrance. Absolutely smothered in delicate clear yellow flowers, it should be lightly trimmed after flowering to aid its bushy growth and hopefully increase longevity.
Boronia heterophylla is grown for its masses of stunningly beautiful bright magenta pink flowers (grown extensively for the cut flower trade). They also have a soft citrus fragrance as a bonus. There is now a white form called ‘Ice Charlotte’ that is equally beautiful.
Quite a lot of breeding has been done with boronias and numerous lovely cultivars and hybrids are on the market and worth looking at. Perhaps the most exciting development is the grafting of boronias to give them a longer garden life. Still new, we are hoping to have these for you as soon as they are released.
Boronia is not easy to grow, and is short lived, but people want them anyway because they are just gorgeous. The trick to growing them is perfect drainage combined with keeping them moist (like Daphne), and the ideal light conditions are dappled light, but I think morning sun and some afternoon shade would be fine. They are shallow rooted, so mulch will help protect the roots. Prune lightly after flowering. Spring is the preferred planting time, although you can plant any time as long as care is taken. Boronias do well in the cooler soil temperatures of Melbourne, so give it a go.
An interesting fact about Boronias is that up to 25% of people cannot smell them at all. Are you Boronia challenged?