"Mistaken identities"

There are several plants in bloom at the moment that are often thought to be Salvias.
Sunday, 21 March 2021     

Brillantaisia ulugarica

Two plants in my garden at the moment are often taken to be Salvia specimens, but they actually belong to quite separate genera, despite their similarity to many of the Salvia I grow. The first is Brillantaisia ulugarica, which I bought with a label proclaiming it to be 'giant blue sage'. However, it is not even in the same general Lamiaceae family as the Salvia, belonging instead to the Acanthaceae family, which includes plants such as Justicia species, Acanthus mollis, Rhinacanthus and Ruellia. Brillantaisia is an imposing soft-wooded shrub from tropical Africa, growing up to 3 m tall in summer, bedecked with spires of intriguing hooked blue-purple flowers. It is in bloom for about six months and makes a bold statement in a semi-tropical style border along with plants such as Salvia, Canna, Dahlia and Amaranthus. The leaves are large and lush green, adding to its tropical appearance.

Mine grows in full sun, but other gardeners tell me that theirs grow and flower in light shade just as well. It copes with very ordinary garden conditions. I have never been able to find a single reference to it in any of my gardening books, though it is listed on internet sites. Thanks to its ease of propagation, it has spread throughout the Sydney gardening fraternity. I cut mine back to within 60 cm of the ground in late August and this seems to help it form a shrubbier shape. It strikes very easily from cuttings taken in the warmer months.

Another plant often mistaken for a Salvia that is in bloom now is Lepechinia salviae. It has large, grey-green textured leaves, shaped like arrowheads; they have a sharp medicinal - though not unpleasant - scent. From late February to May it sends up long spires of burgundy flowers, held in dark calyces on deep pinkish stems. Like Brillantaisia, it is a shrubby perennial, and one that is almost impossible to find in any reference book. Mine grows to about 1.5 m tall and I cut it back hard at the end of winter, when new growth appears at the base. From what little I have been able to find out about it, it possibly originates in Chile and, like Salvia, is a member of the broad Lamiaceae family of plants. There are other species: I have grown Lepechinia hastata in the past, a winter-flowering version, which I did not like as much as L. salviae.

It looks at home grown among Salvia specimens (especially blue-flowered ones) and other denizens of a semi-tropical border. I have mine growing nearby a very dark purple-brown form of Iresine herbstii, which echoes the dark calyces of the Lepechinia blooms. I grow Brillantaisia behind it and this forms a long-lasting composition through late summer and autumn. I grow my specimen in sun, with reasonable soil, but I think they could survive a poorer position.

Another Salvia look-alike is Agastache. There are a few different cultivars sold in the nurseries these days, and with their spires of tubular flowers, they do look very like a Salvia, and also belong to the Lamiaceae family of plants. Some originate in North America, where they are pollinated by hummingbirds, giving rise to a common name of 'hummingbird mint'. Some I have seen are a pretty apricot one (Agastache aurantiacus, ht 90 cm) and a taller one with dusky pink flowers (Agastache mexicana, ht 120 cm). They are said to like dry, sunny spots. I haven't had a lot of luck with them, perhaps because my clay soil is so heavy, but I have seen it growing well in gardens of some of my friends in Sydney.

The Lamiaceae family is a one I am very fond of, not least because Salvia were one of my first plant loves and enabled me to create a cottage garden look with plants that thrive in the Sydney climate! The broad characteristics of the Lamiaceae family, which contains more than 200 genera, include square stems (usually); simple, often hairy, leaves; and two-lipped (usually), four- or five-lobed flowers held in racemes, cymes or whorls around the stem. Bees and other beneficial insects are usually very attracted to the blooms. Many Lamiaceae plants secrete volatile oils, and the family includes herbs such as mint, thyme, oregano, basil, rosemary and culinary sage, as well as lavender, bergamot (Monarda didyma cultivars, though I find them hard to grow in Sydney), lemon balm (Melissa officinalis) and catmint (Nepeta species and cultivars). Other favourite members of the Lamiaceae family are the many sorts of Plectranthus (in bloom now!), coleus, Stachys byzantina, Teucrium hyrcanicum, groundcovering Lamium maculatum, the unusual annual Molucella laevis, the various species of Clerodendrum and shrubby lion's ear (Leonotis leonurus).

It is sometimes hard to come by some of these plants nowadays, but one great opportunity to find such treasures is at the Collectors' Plant Fair at Clarendon NSW, coming up on 10 and 11 April.

Blog first posted 7 March 2010; updated 21 March 2021.

 Reader Comments

1/8  Neil - 3149 (Zone:10 - Mediteranean) Monday, 08 March 2010

Hi Compulsive Gardener, It is great to clear up information where some nurseries get things wrong. We happen to grow each of the plants you mention among our salvia collection- all correctly named. Both Brillantasia and Lepechinia are listed in ABC Gardening FLORA publication.

Thanks for the tip for where to find some written information on those two plants, Neil. Deirdre

2/8  Geoff - 2323 (Zone:10 - Warm Temperate) Monday, 22 March 2021

Thank you Deirdre. I bought my Brillantaisia from a Collectors' Plant Fair several years ago and find it very hardy. Its leaves always look quite lush, except after a hail storm! I have a white form of Leonotis and it, again is very hardy and requires little if any water. I used to have the orange form but lost it over the years. However, I saw it growing in its natural environment somewhere in Africa.....maybe on a safari or in Zimbabwe.

3/8  Bren - 2540 (Zone:10 - Warm Temperate) Monday, 22 March 2021

I picked up Brilliantaisia at a market. It certainly lives up to its name. But I have always believed it preferred shade! I'll try it in a sunnier position.

4/8  Terry - 2072 (Zone:10 - Warm Temperate) Monday, 22 March 2021

Hi Deirdre, I agree that Brillantasia is a great plant. Mine was growing so vigorously in full sun that I feared it would take over, so I dug it up and moved it to my 'rainforest' area where it continues to grow, and flower, in full shade. I purchased mine from the Botanic Gardens Growing Friends plant stall (under the name 'Brilliantasia Nitens').

5/8  Anne - 2518 (Zone:10 - Warm Temperate) Monday, 22 March 2021

have had Brillantaisia for some time. Love the colour. I also have the white version of leonotis. Funny I had trouble remembering the name Brillantaisia and have its name on a yellow sticky inside my front door!!! Hope you and garden are surviving the rain. Not too bad in my part of the Illawarra

6/8  Sue t. - 2566 (Zone:10 - Warm Temperate) Monday, 22 March 2021

Ive tried Agastache several times and they struggle for a while but never look healthy. My soil is probably not as heavy as yours. Be careful where you plant the orange Leonotus. Mine was enormous and hard to dig out.

7/8  Maureen - 2118 (Zone:10 - Warm Temperate) Monday, 22 March 2021

Another great and inspiring read. Love the Brillantaisia which has been much shared.

8/8  Kerrie - 2104 (Zone:10 - Warm Temperate) Monday, 22 March 2021

I got my Brillantaisia from the Growing Friends nursery at the Sydney Botanic Gardens. Just love it! Lepechinia & Leonotis I got from the Plant Collectors Fair so they are out there.

Make a comment

* You can only post comments on Blogs if you are signed in. If you are already registered please go to the Home page and Sign-In first. If you are not an iGarden member please click here to register now.

My eBooks (PDF)

Plant of the week

Most-recent blogs

Plant sculpture
26 Jun 22
Plants with dramatic shapes can provide form and interest during the winter months.

The power of scent
19 Jun 22
Scented plants come to our aid in winter!

Welcome to Ferris Lane
12 Jun 22
A rubbish-strewn lane has been transformed into a lush oasis

Leaves of gold
05 Jun 22
Golden foliage can brighten up a gloomy winter's day.

Unravelling grasses, rushes and sedges
29 May 22
These plant have much to offer but can confuse!

Previously at this time

2009 - 17 Mar
2010 - 21 Mar
2011 - 20 Mar
2012 - 25 Mar
2013 - 24 Mar
2016 - 27 Mar
2017 - 19 Mar
2018 - 18 Mar
2020 - 15 Mar
2022 - 20 Mar

Sponsor message