Many of the iris species must be considered amongst the loveliest subjects of the bulb garden, yet it is remarkable how little known are most of them. Most are suitable for pot culture in the home and it is surprising that more are not commercially grown for sale inwhen they would make a welcome change from the usual tulips and . Particularly am I thinking of the lovely reticulata which will come into bloom in January, reaching a height of only 8-9 in. This is the ‘netted’ iris, so called on account of the strange netted coating of the bulbs.
It will prove an outstanding plant for a rockery where its dainty foliage and habit does not give an appearance of coarseness in any way. The plants are at their best when planted near a rock, particularly if it is a piece of weathered Yorkshire stone, which is greyish white in colour, and which shows off the rich purple, crimson and pale blue colours of the bloom to the greatest advantage. On the rockery or as an edging to a border it will come into bloom mid-February, at a height of only 6-7 in. Planted in short grass where it looks delightful, it will reach a height of 9-10 in. In the semi-shade of trees, particularly amongst the silver birch, with their brightly coloured winter bark, the bulbs may be left untouched for several years when they are best lifted, divided and replanted during September. The bulbs should be planted no more deeply than 1 in – they should be just covered with soil and no more. They love a cool moist soil, which is provided by incorporating some peat or leaf mould, or even some rotted manure into the soil, and they do appreciate a peat mulch early in summer to protect them from a hot sun.
But it is inthat they look at their best. They should be planted six bulbs to a pot in early September, well watered and placed under a covering of ashes just as for other bulbs. There they remain until taken indoors early in November. They must be given only the coolest of temperatures, whether in the home or , in no way will they stand forcing, for it must be remembered that they will bloom unprotected in the open before the end of February. The blooms carry a delicious perfume which will scent a large room, when the blooms are fully open. No lovelier plant will be waiting to greet the new year and being quite inexpensive at least one pot should be in every home.
After flowering the bulbs should be slowly dried off and then replanted outdoors as soon as their foliage has died away. The flower head should be removed as soon as they have passed their best.
- Iris reticulata. This is the native iris of the Caucasus, strongly perfumed – the colour being rich purple-blue with attractive orange marks on the petals.
- I. reticulata Can tab. A superb plant of recent introduction, bearing blooms of a pure Cambridge blue shade, striped orange on the fall petals. Though of a delicate colour the blooms are well able to stand up to winter conditions but are at their best when planted in pots.
- I. reticulata Hercules. A magnificent contrasting colour, the blooms being almost bronze-coloured with beautiful orange markings on the falls.
- I. reticulata Krelagei. An old variety which carries almost no perfume, but it bears a bloom of a warm deep crimson colour. A strong grower of refined habit and slightly earlier flowering than the others.
- Iris alata. The first of all irises to bloom – from an early August planting it will come into bloom in a sheltered border in the open in early November. It likes a dry soil, one well enriched with lime rubble. Flowering at a height of only 8-9 ft. it is also a most suitable plant for a cool-house. It bears a rich lavender-coloured bloom with the lower petals coloured gold.
- Iris Bakeriana. A member of the reticulata section and carrying the same rich fragrance. It is even earlier flowering, coming into bloom in a sheltered corner immediately after Christmas. The blooms are almost of a sea-green shade, blotched and marked with yellow and black blotches. Slightly taller growing than the reticulata, but equally valuable for indoor pot culture.
- Iris Bucharica. This is a lovely species from Bokhara, where the best carpets are made. It bears, in early May, a spray of pale yellow and white blooms enhanced by the rich shiny bottle-green colour of its foliage. It likes a dry, sunny . The bulbs should be planted in October. It is a grand rockery plant but not very suitable for indoor pot culture.
- Iris Danfordiae. Introduced to Britain in 1899, this is another winter-flowering iris. On a sunny February day it may be seen opening its orange, brown and yellow blooms amidst the melting snow. It also does well in pots given the same treatment as the reticulata.
- Iris histroides. Coming into bloom in the open in early March, this is a delightful iris to follow on Danfordiae. The blooms are of brightest blue, crested with gold and it is perfectly hardy even in an exposed position. It is an excellent plant for indoor flowering in February.
- Iris orchoides. A rare and expensive variety, but so beautiful that at least one or two should be planted in every garden. The primrose yellow blooms appear in April at a height of 15 in. and look particularly lovely when planted in short grass under trees.
- Iris sindjarensis. A lovely iris which bears its fragrant violet-grey blooms during March. It is unusual in that its blooms are borne in clusters of three or four on 12 in. long. It requires a well-drained soil and a position where it can be kept as dry as possible such as under a wall or beneath a clump of conifers or cupressus trees. It will bloom well in pots in a cool-house. Outdoors it is best planted in October.
- Iris sisyrinchium. An inexpensive and delightful plant bearing its small purple during April, May and June. The blooms last only a day, but are constantly being replaced by others right through early summer.
- Iris tingitana. A native of Tangier and not quite hardy though in the south-west it will bloom abundantly in the open. It should be given a dry position, one where the summer sun will bake the ground. Should the summer be wet and sunless the bulbs may tend to rot away. Indoors it is a splendid subject for planting in large pots or boxes. The rich deep blue have a vivid orange spot on the falls.
- Mansfield. Of a rich wine purple shade.
- Mont Blanc. Purest white and a strong grower.
- Cajanus. This is a late-flowering variety of a rich golden yellow, valuable in bridging the gap between the Spanish and English flowering-times.
- King of the Blues. A strong grower, producing its deep purple blooms during June.
- La Reconnaissance. An unusual shade for bulbous irises, this variety bears blooms of attractive rich bronze with golden blotches.
- Queen Wilhelmina. Bears a neat white flower which has a small yellow blotch on the fall petals.