The Rock Garden Plants
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Excerpts from the Bulletin
Juno stenophylla and its growing - V. Lajn pg. 135
Both subspecies of this plant the author grows a rock-plant glasshouse situated on southwestern slope of his garden in central Bohemia. It demands stony, very permeable, moderately alkaline soil. The site must be protected against summer rains to secure the good ripening of bulbs, which is an indispensable precondition of good growth of the plant. Its demands are about the same as of e.g. Juno persica.
Juno stenophylla is one of most precocious species of this genus and its subspecies allisonii blooms even a little earlier than the typical subspecies. It also blooms readily and produces more seeds, which are better germinant.
Erodium acaule - L. Kodídek pg. 149
At least since ten years the author grows this plant in his rock garden, which is situated at altitude of about 350 m. It demands a plot deflected from the direct noon sunshine and permeable stony soil with minimum content of humus and calcium. It need not to be covered in winter.
It blooms luxuriantly and for a long time, from the end of May to the coming of frosts. About 50 per cent of flowers produce seeds, which after ripeness are “shot out” into the surroudings. In spite of it, this plant does not show any tendency to turn into weed, because the spontaneous seedlings are not numerous. The seeds are to be sown in autumn or in early spring. The propagation is also possible in vegetative way by separating of lateral rosettes in spring or in autumn. They must be then kept under glass.
How to manage the rock garden ? - S. Čepička pg. 168
The rock gardeners often visit me to ask advice what they should grow in their rock garden. I have devoted myself to this hobby already over twenty five years. My garden lies in central Bohemia about 200 m a.s.l. on southwestern slope, where it is exposed to sunshine from 8.30 a.m. to 6 p.m. The soil is formed by disintegrated schist.
I explain them that the choice of sortiment is most important. I depict them my errors arisen from lack of experience, when I tried to grow various cold-loving and hydrophilous plants which I liked, but which weren't suitable for this type of biotope. Only repeated failures led me to the idea to grow first of all the tuberous and bulbous plants from the Balkan Peninsula, Central Asia and other warm and dry regions.
All gentians and other cold-living plants I gave to my brother, whose rock garden lies in a higher site. The results were evident within a short time. All plants recovered as sprinkled with elixir of life. The change of sortiment has proved to be very good in my garden, too, so that I have grown these plants already for a long time all years round without winter covering.
Many rock gardeners ascribe my recent successful results mainly to the chemical composition of the schist mentioned above, thanks to the balanced ratio of magnesium, calcium and phosphorus. I know, however, that for the thriving condition of them in first place the permeability of substratum and intensive insolation of my garden are responsible.
Arisaema dracontium - J. Šlégl pg 150
The Arisema species appear more frequently in Czech gardens in the course of the last years. Beside Asiatic species, also two North American plants are to be seen among them, viz. Arisaema triphyllum and A. dracontium.
The author obtained four seeds for A. dracontium in January 2003 from Canadian seed exchange. He sowed them at once and waited, whether they would germinate in spring. This happened at the beginning of June. Before winter he precautiously transferred the small tubers into cellar. In spring 2004 he was surprised by one plant which came into bloom and even produced fruits. At the beginning of hibernation he took out one tuber and planted it into humose earth in the grove part of my garden, the other one he kept in the container. In this year both plants already bloomed and produced fruits, too.
Rock plants of the genus Anthyllis - D. Hetzerová pg. 147
Recently the author grows in her rock garden in central Bohemia two species of the genus Anthyllis, viz. A. montana and A. vulneraria in red form. She grows the both plants in a insolated site in permeable soil and do not provide them with winter covering.
A. montana she propagates both by cuttings and by sowing, because it sometimes produce fertile seeds in her rock garden.
A. vulneraria, however, sometimes must be limited by slipping of some fruits to prevent the excessive spreading of them.
Several times she grew in the same way also A. hermanniae. This species, however, never survived three years, even when covered in winter.
Allium insubricum or Allium narcissiflorum ?- E. Hanslík pg. 152
The author treats differences between these species and reports his experience with the cultivation of them. The plants demand sandy-loam soil (ratio 1:2) in site exposed to sun. The presence of calcium or limestone or dolomitic stones in soil is favourable for plants, fertilizing is to be recommended, too. The separating of the bunch of bulbils in spring must be made carefuly to prevent the damaging of the rootstock below them. The
Penstemon species in my garden - M. Mally pg. 145
The author grows Penstemon caespitosus on slope exposed to sun in earth containing small stones with addition of pine litter and sand (ratio 1:1:2). This plot is partly covered with a terrace and moreover it is covered with foil in winter. The plants are popagated by separating the rooted parts in early spring. Fertile seeds are not produced.
In a similar plot also P. davidsonii is grown without winter covering. The seeds are produced in sufficient amount, but the author propagates this species only in vegetative way by taking herbaceous cuttings with woody bases, which he then keeps under glass.
P. hisrutus var. pygmaeus is a tenacious plant, which grows in various places of the rock garden. It keeps up by rich spontaneous sowing.
Iris verna ? - M. Lhotská pg. 161
The author points to the characters by which the species Iris lacustris and I. cristata are different from I. verna, which they are often confused with.
As regarded their cultivation, they are undemanding and longlived plants. I. cristata grows on the top of the author's limestone rock garden in central Bohemia. I. lacustris has been planted in garden earth in a place protected from noon sunshine. They don't produce any seeds in the culture, they are propagated by dividing of rootstock in early spring or after blooming.
Helianthemum for small rock garden - A. and O. Beneš pg.158
Of the low-growing Helianthemum species, the authors cultivate in their rock garden in central Bohemia (altitude 300 m) Helianthemeum canum and H. oelandicum ssp.alpestre.
Both species have been cultivated in a sun-exposed site in permeable and not very nutritive substratum. The production of seeds has not bee observed in them as yet. They are propagated in sowing of seeds from natural localities in a sowing mixture in January or by herbaceous cuttings taken at beginning of June and kept in a substratum mixed of coarse sand and peat (ratio 1:1).
New plants in my rock garden - Z. Řeháček pg. 138
The autor reports on the cultivation of new plants in his rock garden in northeastern Bohemia (500 m s.s.l.).
Aethionema caespitosum. He planted this species twice in his rock garden, but his pleasure in both cases was short. Even when he planted it in the second case in a site protected from noon sunshine, it did not help, and the plant died away in summer,
Alyssum caepitosum. The author grows it on the southern slope exposed to sunshine in well permeable earth, no cover is used for winter. As it produces no seeds, the author propagates it by cuttings from June to August. The plant pictured here is already 8 years old.
Androsace rigida. After several years of growing the author has stated that this plant can be grown rather easily in pots with permeable substratum, providing that it hibernates in glasshouse. The planting in his rock garden, however, never was successful. It produces only few seeds. The author propagates it by cuttings and partly by sowing.
Brachycome aculeata. The plant was grown on the steep northwestern slope in acid part of the rock garden. It lived for several years there and bloomed twice or three times. However, it did not produce any seeds, and during one rather hard winter it got lost without replacement.
Corydalis buschii is grown in a heath plot exposed to sun from 10 a.m. The winter it survived uncovered, its bunch is permanently growing, so that the author intends to divide it.
Dianthus versicolor. This plant comes from drier habitats, so that the conditions of author's garden were not favourable to it. Once it bloomed, but then it did not survive the moist autumn and winter. It produced no seeds.
Erigeron elegantulus demands drier sites especially in summer. It does not tolerate the presence of calcium in soil. In a sunny, well-drained site it kept up for 4 years.
Minuartia circassica. In the author's opinion, this species can be grown without any problems. It demands only sunny site and otherwise normal conditions.
Primula minutissima is a plant which the author has grown already for 12 years, but it has not bloomed as yet. He replaced it twice by new cuttings, planted it in pot with permeable soil placed in a possibly cool site and still is hoping to see it come in bloom.
Ranunculus brevifolius grows reliably on the northern slope of author's rock garden in permable earth. Every year it regularly comes into bloom and produces several fruits.
Veronica grandiflora was grown by author three times, but only in the third attempt it bloomed. However, its flowers were not so big as given in the literature. In no case it survived the summer heat.
Viola alpina. This viola species is cultivated exclusively in crevices of a travertine rock situated on the northern slope. This year it produced first seeds, which were sown.
Veronica armena - M. Blažková pg. 159
The author grows this plant in several sites of the eastern and western slope of her limestonne rock garden in central Bohemia (altitude 200 m). It has been planted in permeable earth, in winter it is not covered and during the sultry weather is watered in the common way, mostly in late evening.
It produces only few seeds, the spontaneous sowing occurs rarely. The author propagates it successfully by making cuttings (about 8 cm in lenght) from not-blooming stems in spring or at beginning of autumn.
- The Rock Garden Plants - #2