Over-the-top cactus flower extravaganza (2 of 2)

The cactus flower extravaganza in my friend Justin's East Bay garden continues below. Click here to see part 1, Astrophytum to Lobivia.

At the bottom of this post, Justin shares some growing tips, including soil, watering, and fertilization.


Mammillaria
With over 200 species, one of the largest cactus genus and quite possibly the most collected. With some exceptions (like M. dawei and M. guelzowiana below), Mammillaria typically have small to very small flowers, but there are often many of them forming rings around the body of the plant.

Mammillaria bombycina

Mammillaria bombycina

Mammillaria compressa

Mammillaria dawei

Mammillaria elongata

Mammillaria fittkaui

Mammillaria grahamii

Mammillaria grahamii

Mammillaria guelzowiana

Mammillaria guelzowiana

Mammillaria guelzowiana

Mammillaria matudae

Mammillaria microhelia

Mammillaria microhelia

Mammillaria mystax

Mammillaria mystax

Mammillaria perezdelarosae

Crested Mammillaria pringlei

Crested Mammillaria pringlei

Mammillaria saffordii

Mammillaria saffordii

Mammillaria spinosissima


Notocactus
Notocactus was subsumed into Parodia in 1984, but this decision is still controversial and many collectors continue to use the old names. In this post, I’m following the naming preferred by collectors rather than taxonomists.

Notocactus sp.

Notocactus sp.

Notocactus sp.

Notocactus sp.

Notocactus sp.

Notocactus herteri ssp. roseoluteus

Notocactus herteri ssp. roseoluteus

Notocactus herteri ssp. roseoluteus

Notocactus herteri ssp. roseoluteus

Notocactus magnificus

Notocactus ottonis

Notocactus schlosseri

Notocactus schlosseri

Notocactus tabularis

Echinocactus grusonii, Mammillaria mystax, Notocactus uebelmannianus

Notocactus uebelmannianus


Obregonia
The genus Obregonia has only one species, Obregonia denegrii, aka the artichoke cactus. It’s one of the most unique-looking cacti and easy to recognize. Wikipedia aptly describes it an “inverted green pine cone with a woolly center.”

Obregonia denegrii

Obregonia denegrii


Parodia
In the broader sense, Parodia includes Notocactus (see above). All are native to the uplands of Argentina, Peru, Bolivia, Brazil, Colombia, and Uruguay.

Parodia microsperma

Parodia microsperma

Parodia microsperma

Parodia microsperma

Parodia microsperma

Parodia microsperma (formerly P. sanguiniflora)


Rebutia, Sulcorebutia
Now included in Echinopsis, but generally still labeled as Rebutia or Sulcorebutia in nurseries, plant shows, and collections. These small cacti from Bolivia and Argentina are prized for their large and colorful flowers.

Rebutia or Sulcorebutia sp.

Sulcerobutia sp.

Sulcorebutia sp.

Stenocactus
A small genus of cacti from Mexico with thin and often wavy ribs. Now includes the species formerly in Echinofossulocactus.

Stenocactus multicostatus


Tephrocactus
Tephrocactus are easy to recognize by their round or cylindrical stem segments and papery spines (or no spines at all). The segments break off easily and root readily. Like all other members of the subfamily Opuntioideae, Tephrocactus have glochids, so careful when handling. Large and showy flowers.

Tephrocactus articulatus var. papyracanthus

Tephrocactus articulatus var. papyracanthus


Thelocactus
Native to southern Texas and northern and central Mexico, Thelocactus are popular because of their beautiful flowers.

Thelocactus bicolor aka glory of Texas

Thelocactus bicolor

Thelocactus bicolor

Thelocactus bicolor

Thelocactus hexaedrophorus

Thelocactus hexaedrophorus

Thelocactus panarottoanus

Thelocactus setispinus

Thelocactus setispinus


Tunilla
A small genus of opuntia relatives from Argentina, Bolivia, Chile, and Peru. Uncommon in cultivation.

Tunilla soehrensii

Tunilla soehrensii


Cactus growing tips from Justin and Gerhard

In general, cacti are easy to grow and require little care beyond occasional watering—as long as you lay the right groundwork. It all starts with...

Soil

The most important thing about soil is that it's well draining. Sandy loam work best. An easy way to check your native soil is to take a handful of wet soil and try to make a ball. If it falls apart, you're good; if it holds together, you need to amend it with inorganic matter such as pumice, small pea gravel, lava fines, etc.

For in-ground plantings, the best solution by far is to make mounds of premixed succulent soil right on top of your native soil. Justin uses Bancroft Bedding Blend from Contra Costa Top Soil in Martinez. Check your local rock yard to see if they have any succulent blends; if not, start with a general-purpose garden soil and work in inorganic materials like the examples mentioned above.

Fertilizer

Succulents aren't heavy feeders and plants in the ground typically don't need much extra fertilization. Justin adds bone meal to the soil when he creates new mounds or pots up new plants. Cactus receive a dose of bloom fertilizer 1 or 2 times a year.

Watering

When possible, keep cacti as dry as you can in the winter—cover with a tarp during heavy rains or move pots under eaves, onto a covered porch, etc.—or give them a resting period (no watering) before the winter rains.

A simple rule of thumb: Water consistently when hot. Don't water at all when cold.

Cold hardiness

Some cacti are hardy down to 0°F or even below, others barely tolerate temperatures in the low 40°F. It's impossible to make general statements about cold hardiness, so you need to do some Googling about each species (if you're lucky, your plant came with that kind of info on a tag or label).

Most importantly...

Enjoy what you already have, add to your collection whenever you can, and have fun. Consider joining a local cactus and succulent society to hang out with like-minded people and learn new things.



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Comments

  1. Justin's garden must be quite a sight with all the cacti blooming. The colours are so brilliant. I guess when you are a small plant in a wide open desert you need those gaudy brilliant colours to attract attention. Thanks for this great tour.

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  2. Lots of beautiful things happening in Justin's garden. There's something about the bright jewel-like colours of cacti in bloom; you rarely see those colours in other flowers. Thelocactus bicolor looks like exploding fireworks - wowee! Thanks for the tips re cacti care.

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  3. Enjoyed your colourful, photo intensive post. Quite a contrast to see those cactus with crowns of flowers

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  4. So many flowers! Wowsa. Now I am especially bummed that my Obregonia denegrii turned to mush.

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  5. So now I’m having a major attack of “cactus intoxication”. Main symptom is uncontrollable desire to buy more plantsšŸ˜Š

    ReplyDelete

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