This section is from the book "Handbook Of Hardy Trees, Shrubs, And Herbaceous Plants", by W. Botting Hemsley. Also available from Amazon: Handbook of hardy trees, shrubs, and herbaceous plants.
Under this head we refer to Ranunculus Asiaticus and E. Africanus, and Anemone Coronaria and A. hortensis, the progenitors of the numerous florist's varieties in cultivation. The permanent rootstocks of these plants are composed of fascicled fleshy tubers, and they are here associated with the bulbous plants simply on account of their being capable of sustaining life for a considerable period out of the ground. Indeed, they will retain their vitality for one or even two years in a dry place, if protected from frost. The successful culture of these plants is attended with considerable difficulty, and this is especially the case with the double varieties. The single-flowered Anemones are, however, hardier, and require no more than ordinary attention. A few years back the choice double-flowered varieties of both Anemone and Ranunculus were extensively cultivated, but at the present time they are comparatively rare. This is probably the result of exaggerated notions regarding the difficulties attending their culture. These are by no means so great as is generally supposed, though doubtless they are sufficient to cause those with little time on their hands to shrink from encountering them. One thing is absolutely necessary to ensure good and abundant flowers, and that is annual lifting after the flowering season, when the leaves begin to die off. Otherwise they are apt to start again and flower in the autumn, rendering the chances of spring-flowering doubtful. A deep, free, well-drained soil, copiously manured with thoroughly rotten cow-dung, or from an old hot-bed, is also essential, with the addition of leaf-mould and sand, according to the nature of the ground in question.
Anemones prefer a somewhat lighter soil than Ranunculuses, but both will flourish where the above conditions are attainable. It is customary to grow them in beds or borders by themselves, and when these are artificially made, the best material to select is turfy loam that has been stacked and turned about until the herbage is decomposed. The inclination of the ground should be towards the south or east, and the situation tolerably open, that is to say, sheltered, but not shaded. Anemones for the principal flowering should be planted in September or October. If planted in spring they produce a far less luxuriant growth. The proper depth is about three inches, or rather less in a compact soil. The Turban Ranunculuses may also be planted in autumn, but the Persian, being rather tenderer, should be deferred till early spring. Ranunculuses prefer a cool, slightly retentive soil, but the drainage must be efficient. Watering is sometimes necessary, and should be carefully done. Protection from frost should be afforded, or the foliage and inflorescence will suffer. Another condition is firmness of the soil around the roots.