This is a very useful species from southern United States and Mexico. Somehow it got the name autumn sage in the U.S. which is rather a silly name as it blooms from September to May in Australia. It stays pretty much as a small bush. Microphyllas are similar but they are larger, more open generally and inclined to sucker. I have ‘Martine’ here as a greggii but it is closer to a microphylla I think.
Greggii are very hardy evergreens with very pleasantly smelling smallish foliage. They come in a large amount of shades of pink, red, apricot, yellow, white. No blues although a couple of similar plants are blue but are usually hybrids or another species. There are also lots of varied bicolors.
Greggiis set seed readily which may vary and which people pass on so we have a large amount that are often similar and can lead to confusion in identity. Nurseries in particular breed new varieties but usually they have microphylla in them and are bigger plants. A few are patented but because there are similar plants happening it could be hard to prove which plant is which unless you have obtained it from a reliable source. Some variations are in interesting colours but don’t flower as long usually with some microphylla in them. Some are seedlings from named varieties overseas which correctly should not carry the same name unless they have been imported as plants.
Greggiis can be exceptionally colourful September/October when it has masses of blooms especially if you haven’t pruned it right back in the last few months. It can be halved after that first big flush if you want to tidy it.
The best time to prune greggii is in summer after a flush of flowers. Heavy pruning in autumn could lead to a plant dying in a frosty area. Otherwise they are hardy to about minus 10C. They don’t really like humidity so might not live as many years in sub tropical regions. Microphyllas are more tolerant of humidity. They will live 10-20 years or more in inland Australia. I find greggiis amazing because they can be so dry they are shrivelled and look dead, but can return to normal life. I don’t encourage you to do it deliberately though! They are not hard to grow from cuttings.
Greggii ‘Desert Blaze’ This is an imported plant with variegated yellow and green foliage. The flowers seem slightly larger than other greggiis and a rather lovely bright red. As with all variegated plants you must cut sections off that grow green foliage, otherwise the green will dominate. It is probably not that easy to come by. Being variegated it is slower to grow than an all green plant which is able to absorb more sunshine and food.
Greggii ‘Sierra Pink’. (Above in the banner.) I named this seedling which originated with seed from ‘Sierra de San Antonio’ I gathered at Betsy Clebsch’s early in the 1990’s. Another one from this same seed I named microphylla ‘Sensation’. I wish now I had left it as a greggii but I was very inexperienced at the time.
‘Sierra Pink’ is a strong plant and has been used in breeding quite a bit in Australia by Plant Growers Australia so that they offer Sierra this and that in various ranges. They got the plant from me not long after I introduced it.
Greggii orange. The plant I introduced as greggii orange came from seed that a girl near Tucson shared with me. I had a lot of fun down there and like to have it as a souvenir. At the time I introduced it orange was very out of favour in the Australian gardening scene and I didn’t give it a lot of attention. Orange is pale. ‘Kate Shann’ (microphylla) is a bit darker.
‘Tangerine’ came out of the same batch but it is a solid colour. Other people besides myself really like the idea of tangerine and I never have enough plants to supply the demand. ’ ‘Tomato Red’ is very close to tangerine.
‘Grace’ is a pretty pale pink. ’Peter Vidgeon’ is almost identical in colour. However it seems to have a little microphylla in its breeding so is not quite as neat a grower as straight greggii.
‘Ribambelle’ is one of the more recent imports which I really like. It is a soft apricot colour.
Greggii white is a good plant .