What is the proper treatment of Alyssum (Aurina) saxatile which has grown "leggy"?
It is best to raise new plants from seed. This plant does not usually last much longer than 3 years. It is inclined to rot away during winter. If it survives, wait until new shoots appear near the base of the plant, then cut the leggy, long ones away.Does aubrieta remain in bloom for a long period?
No. Its blooming season is short. However, it flowers in very early spring and is worthy of a place in the garden.Are the plants called cinquefoils suitable for the rock garden? Can you suggest a few?
Many cinquefoils (potentilla) are excellent, others are worthless weeds. Potentilla nepalensis, tridentata, and verna are wroth trying. Give them full sun and well-drained, gritty soil.How best to grow pinks in the rock garden?
Dianthuses do best in a well-drained, sunny position. Do not make the soil very rich (most seem to do best in a slightly acid to near-neutral soil) and do not overwater them. They are good on gentle slopes, planted so that they can spread over the top of a rock, or in flat, well-drained pockets. Start with young, pot-grown plants if possible, and plant them out at about 9 ins. apart. Some kinds die after a time, so it is best to keep raising a few fresh plants each year.What kinds of dianthus do you suggest for a rock garden?
Dianthus deltoides (maiden-pink), plumarius (grass-pink), gratianopolitanus (cheddar-pink), and neglectus (glacier-pink).What can I do to make Gentiana andrewsii grow?
It appreciates a moist, semi-shaded situation, preferably on the edge of a pond, and a deep, humusy soil. Topdress in spring with peat moss mixed with a little dried cow manure.Which irises are suitable for the rock garden?
Iris reticulata, gracilipes, pumila (in many varieties), dichotoma, cristata, cristata alba, lacustris, tectorum, and its variety album.What conditions do primulas need in the rock garden?
A rich, moist soil and a shady or semi-shady situation. Some, like Primula pulverulenta, grow best in almost boggy conditions along the sides of streams. Practically all need plenty of moisture. If very moist conditions cannot be given, grow them in shade.Will you suggest some primulas for the rock garden?
Primula polyantha, veris (the cowslip), bulleyana, denticulata, frondosa, and japonica.What care should be given leontopodium raised from seeds?
The edelweiss likes a well-drained, limy soil, full sun in spring, semi-shade in summer, and light protection in winter. Either evergreen boughs or salt hay should be used, as leaves pack too hard and keep the plant waterlogged, which may result in rotting. From seed they should bloom well the second year. Carry the plants over in a cold frame, in pots, the first year.Will you name a few penstemons that would grow in my rock garden? Are they difficult to grow?
Penstemon alpinus, heterophylus, rupicola and unilateralis. These are not difficult. They require gritty soil and do not like a position that becomes sodden in winter. They are not long-lived plants and in order to maintain them it is best to raise a few each year.What soil is suitable for Phlox subulata?
Any light, well-drained garden soil.Where does Phlox subulata grow wild?
In the eastern, western, and southern parts of the United States, on dry banks and in fields.Do most of the western species of phlox require loose, rocky conditions in the eastern states?
Yes, they seem to do better under such conditions in the East.What are some good kinds of phlox for a rock garden?
Some of the most suitable besides the various varieties of phlox subulata are Phlox amoena, divaricata (and its variety laphamii), douglasii, and stolonifera.What is the best place in the rock garden for saxifragas? What kind of soil?
A partially shady situation facing east or west. Soil should be gritty, open, and well-drained. Mix garden soil, leaf mold, and stone chips, or screened cinders, in about equal proportion, and have a foot depth of this in which to plant. Limestone chips are also beneficial.Which saxifragas are not too difficult to grow?
Saxifragas paniculata, apiculata, cochlearis, rosacea (a mossy type, requiring partial shade), hostii, macnabiana, and moschata.How many species and varieties of rock-garden sedums are there?
Approximately 200. Perhaps not more than 50 distinct and useful kinds are available in nurseries.Which are the best sedums?
Sedum album, anglicum, brevifolium, caeruleum (annual), dasyphyllum, ewersii, kamtschaticum, lydium, nevii, oreganum, populifolium, pilosum, rupestre, sexangulare, sieboldii, spurium ternatum, stoloniferum, hybridum, and the self-sowing biennial nuttallianum.Can I get information regarding the culture of sedums?
Most are easily propagated from cuttings taken in the fall or spring. They root best in sand, either in flats or in cold frames. When well rooted, transfer them into small pots or put them directly into their permanent places in the garden. The location should ordinarily be sunny, the soil sandy and well-drained. Western-America sedums prefer a semi-shaded position.Are the sunroses (Helianthemum) hardy? Do they require much care?
They are not very hardy; they thrive fairly well in the vicinity of New York but farther north they are doubtful subjects. They need no more care than ordinary rock-garden plants. Give them a well-drained soil in a sunny location. Protect them in winter with salt hay or evergreen boughs, and cut them back to within a few inches of their crowns in spring, to encourage fresh growth.