W is for Watsonia. I absolutely love this spring blooming bulb. But it has some bad habits. Not all of them. Not all Watsonias. But there is one that can act like the black sheep in the family, and run amok and run crazy.
In fact, I think I saw it in Bolinas, (a cute coastal town north of San Francisco) a couple of weekends ago growing in thickets, in a riot of color naturalizing right on the coastal bluffs. So pretty. I couldn’t help clicking away with my camera.
But then I thought, “Uh Oh, this might not be good, an invasive species?” Some plants can get just too happy and take over.
Not just in your garden, which can be a huge pain in your butt – you’ve done that right? How about when a plant, like this black sheep Watsonia, goes into sensitive natural areas (like the coastal bluff), an area where nature touches residential areas. Where those two environments have some blending going on, due to proximity?
Not good!
I is for Invasive
Well, like I said, only one species of Watsonia (Watsonia meriana aka: wild watsonia) is on the invasive plant list, which I searched for at the Invasive Plant Atlas. Great resource by the way. You should definitely check it out if you garden in the USA.
To get a better understanding of what an invasive plant is, the California Invasive Plant Council says:
Across California, invasive plants damage wildlands. Invasive plants displace native plants and wildlife, increase wildfire and flood danger, consume valuable water, degrade recreational opportunities, and destroy productive range and timber lands.
Getting back to wild watsonia (Watsonia meriana) Wikipedia says:
It is well known as an ornamental plant grown in gardens for its showy spikes of flowers and an invasive species in areas where it has escaped cultivation.
What can you do? check this out.
About Watsonias & I Confess to Being a Spring Time Watsonia Plant Stalker
Blooming Watsonia flowers were also one of the highlights in several adorable gardens I peeked into. I have several photos to show you. There are a couple taken last week at the UC Bot Gardens too. They are planted in the South African section, surrounded by amazing succulent plants and others that do well in a mild Mediterranean climate, a definite Nicole passion (that’s me).

Watsonia with hummingbird, UC Bot Gardens, June 2015
About Watsonias
This stunning ornamental plant is a cormous perennial (yup, like a bulb but a corm) and is native to South Africa. You can find many species and hybrids ranging in size from dwarf to those growing large and producing thickets. Also, some are sturdy and evergreen, while others die-back and are deciduous.
But the main thing is that you can enjoy them planted in a variety of sunny places: Tall ones for back of the border or naturalizing down a garden hillside; smaller and dwarf ones to combine with perennials and grasses, or enjoy in a container.
All of the Watsonias make excellent cut flowers. They also provide a yummy nectar source for hummingbirds and bees, so you’ll attract more life to your garden!
If you like Gladiolus, plus you like Watsonias, you may have a bias towards the Iris family. Both of these plants come from the Iris or Iridaceae family. However, you’ll find that Watsonia flowers generally are smaller and more tubular on taller, branched stems than the flowers of Gladiolus.

Enjoying life! Me and white blooming Watsonia in Bolinas, CA
Here are Several Watsonia Species and Hybrids
- altetroides – Small species, with 8 -12″ leaves and a 1′ to 1.5′ flower stalk. The plant appears in fall and blooms in mid to late spring. Moderate water while growing and blooming. Color can range from deep coral pink to scarlet.
- beatricis hybrids – Distinguished by its large thickets and narrow 2 foot fans of dark, evergreen leaves. Three inch blossoms open in summer along dense spikes up to 5′ tall, the show lasting many weeks. ‘Rose’s Flame’ – flame orange blossoms. Others range from wihite to crimson in color.
- coccinea – This one is perfect for a container or small garden. It respects the boundaries and isn’t a spreader. Does well in Mediterranean gardens with dry summers. Dormant in summer and growing in winter and spring when the natural rainfall occurs. Not picky about soil, but good drainage is still suggested. Drought tolerant. USDA Zones 8-10
- Dow hybrids – Flower time is late spring to early summer. Following that they are mostly summer deciduous so the foliage will die back. Flower spikes are 3′ high with 3″ blossoms colored pink, red, white, mauve. Normal fall to spring rain should satisfy their requirements. Hardy to 10 – 15 degrees.
- galpinii – Flower time is summer. Robust species with 1′ leaves and flowering stalks 3′. Flower color: brilliant red-orange on branched spikes. Hardy: 20 -25 degrees.
- humilis – Dwarf species with broad 4 to 6″ fans of leaves and 8 to 12 stems.

Watsonia in Bolinas
Happy Gardening!
ps: We didn’t forget – you want to know where you can get your hands on Watsonia. If you’re in the Bay Area – Annies Annuals is the place to go (Warning! – this place can be dangerous to your credit card as it is an enormous sea of gorgeous flowering plants), and if you’re not in the Bay Area, they offer mail order. Passionate Gardeners is not affiliated with Annie’s Annuals – we just think they’re great.
For Bulbs, another mail order option is: easytogrowbulbs.com
And, if you are planning to order a lot of bulbs, the Yard Butler Bulb Planter on Amazon will make your life a whole lot easier. The nice thing about this tool is that you don’t have to bend down and you can leverage your weight to get into the soil.
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