I like frostproof North American species, and among them I particularly like the kind Navajoa. It is small globular cactus, which is native to northern Arizona.
Description and sowing
Its pride are white to brownish cork spines that are hollow and are used to capture the morning dew. The main growing season is short and falls into the spring months. At that time, plants are flowering with yellow flowers, slightly off-white or pinkish flowers, and soon after flowering make fruits, which mature in lengthwise cleft. It should then be guarded and the seeds should be collected several times a day. Seeds are relatively large, but usually not completely happy germinate. We can persuad them to sprouting by heating on the radiator or stove at 60 ˚C prior to planting, bathing in acid or peroxide. Previously recommended overfreezing of the sowings seems to me like the least efficient. For the most reliable method I consider scarification*. This way I managed to get of the 120 seeds sown 120 seedlings (but not counting the seeds I ruined by careless handling) ...
Navajoa are prone to different soil fungi. Therefore, I recommend to graft at least the first plants in the collection to ensure offspring. For fresh seedlings, as a temporary base, peireskiopsis, selenicereus and echinopsis are suitable. Nowadays I graft on the echinopsis. Growth is slightly slower, but I do not see it as a disadvantage. As a permanent stock I use frostproof Echinocereus - reichenbachii, viridiflorus var. cylindricus or triglochidiatus.
These rootstocks "sit" under the grafts after some time and then the plants look like own root. It is better to graft a small branch on a small Echinocereus.
Then the plants better keep miniature look. Sometimes, offshoots from the grafted plants on peireskiopsis then quickly outgrow the grafting size and from these offshoots, after re-grafitng, are soon outgrown plants. The best time for grafting is early spring, just after taking a drink base. After the grafting Echinocereus don't need much watering not to suck water too much. Should there be any offshoots, cut them off immediately. During the summer dormancy period - from about mid June to late August - there is not need of watering at all. If we have already secured mother plants, we can try to grow some rooted plants (from the seeds, of course). I have been trying this for a long time, more or less unsuccessfully. But those few plants that survive, I consider the most beautiful. Critical period is throughout the life of plants. In particular to take heed of growth, it is necessary to take heed of growth and rest periods.
Replanting is the most critical. The most appropriate term for that is the end of winter, when it is not too hot, so then plants can grow the season root during the spring. If we replant later, it is too hot and the plant stops in vegetation. Also, we water the plant in an attempt to save it, however, on the contrary, we kill it. For a habitat for navajoa we chose the sunniest, but well ventilated places. Suitable is also a free culture available with some protection against the prolonged rain. A unique feature of thorns is advantageous in sunny Arizona, but in the local wet climate (Czech Republic), it is not. Hygroscopic spines still suck water from the air and then unsightly blackheads (kind of mushrooms) settle on them. Although not directly harmful, it certainly disfigures the plant. I tried spraying by Orthocid last year, however, I did not noticed any significant improvement. Plants grown outside the greenhouse should not suffer from this infirmity.
To someone all navajoa may seem almost the same. However, differences can be seen among the same species from different locality, although the variability of plants from one locality is significant.
I have in my collection these Navajoa:
- N. peeblesiana Holbrook, Az - a short, strong, yellowish, mostly only slightly twisted, initially marginal spines, pink flower.
- N. peeblesiana SB 571 Navajo Co, Az - dtto, long spines.
- N. peeblesiana FH 053.1 Marco Mesa, AZ - dtto, robust, spines white, more twisted.
- N. peeblesiana fickeisenii v FH 051.0 Hurricane Cliffs, Az - a small, compact, short fringe, short straight central spines facing up, flowers dirty white to yellow.
- N. peeblesiana fickeisenii v FH 051.2 Wolf Hole Az - dtto, slightly curved central spines.
- N. peeblesiana v fickeisenii RP 145 Mohave Co, Az - dtto obviously the same locality
- N. peeblesiana v fickeisenii SB 468 Fredonia, Az - a long white central spines above the top of intertwined short marginal spines thin, yellow flower.
- N. peeblesiana v fickeisenii SB 903 Houserock Valley, Az - a more robust body and a strong central and peripheral spines gray, off-white flower (strong marginal spines differs from other fickeisenii, he might have deserved this form of self-evaluation of taxonomic subspecies level).
- N. peeblesiana v Maia south of Cameron, Az - short white spines, middle bent and pressed up to the body, yellow flower.
- N. peeblesiana v Maia JB 6 north of Cameron, Az - a thin yellowish spines against his body, off-white to yellow flowers.
- N. peeblesiana menzelii JB v. 2 south of Grand Canyon, Az - yellow thick peripheral and central spines protruding from the body, off-white flower with a brownish central stripe.
- N. peeblesiana v menzelii RP 116 Hualupai Hilltop Area, Az - dtto, white strong spines more curved to the body.
- N. peeblesiana v menzelii RP 117 Coconino Plateau, Az - dtto, longer thinner spines yellowish, slightly curved, tangled over the top.
By Fritz Hochstätter Navajoa kind represents a single species - peeblesiana with three subspecies: ssp. peeblesiana, ssp. menzelii and ssp. fickeiseniorum. The author considers N. Maia as synonymous N. peeblesiana ssp. peeblesiana. In my view, it is closer to ssp. fickeiseniorum.
Some authors classified Navajoe in the kind Pediocactus, which is embedded in this family very well by having very similiar flowers, fruits and seeds.
All Navajoa are very rare in their homeland and they are classified as endangered species in CITES, Appendix I.