This section is from the book "The Gardener V1", by William Thomson. Also available from Amazon: The New Organic Grower: A Master's Manual of Tools and Techniques for the Home and Market Gardener.
These are handsome dwarf evergreen shrubs from New South AVales. They are nearly all compact free-flowering plants, that form most attractive objects for a long period in summer in the greenhouse. The best and most popular kind, perhaps, is B. serrulata, the excellent habit and free-flowering quality of which render it admirably adapted for exhibition purposes, though it is not now so often seen in collections of hard-wooded greenhouse plants at flower-shows as it once was and still deserves to be. A selection of Boronias might be made that would flower almost the whole year round, but it would embrace several of the least interesting and pretty ones: the most ornamental are B. Drummondii, pinnata, tetrandra, anenioncefolia, and serrulata; and of these, were I confined to a selection of two, I would prefer the first and the last. They like good sandy peat, with which- a little sandy fibrous loam may be mixed, and thorough drainage. Greenhouse temperature and general conditions suit them well; but in spring, when making growth, they will bear, and be the better for, a temperature intermediate between the greenhouse and the stove. After growth is made, they should be placed in a cooler place to mature.
In winter the minimum temperature should not be lower than 45°; and considerable care in watering during the dull days of winter is requisite. Cuttings of partially-ripened shoots root freely in sandy peat in a cool propagating-house under a bell-glass, which should not be kept too close. They should not be hastened in any way, being rather slow to root; nothing is gained by pushing them with heat. When rooted, there should be no hurry to pot them off; the roots are easily broken when handled very soon after they have been formed. Large shifts ought always to be avoided with these as with nearly all hard-wooded plants of slow growth. Staking, though often practised, is both unnecessary and an evil. Plants so compact naturally require only a little attention to stopping in their first stages of growth annually, to make them all that can be desired by true art.