The South African orchid. Disa Uniflora and its hybrids, produce some of the most beautiful flowers in the orchid family. The flower range from white through to red, pink, yellow and orange. The flowers can last up to ten weeks in flower.
Disas produce a rosette of leaves, which if the plant is large enough will produce a flower spike. After the flowers have finished, you will see lots of offshoots around the base of the plant, then in September these can be removed and potted on separately. The old plant will eventually go yellow and die but not before producing many new plants.
LIGHT:Disas need adequate light to produce strong plants and flowers, but their roots must be kept cool at all times. They can make an ideal window sill plant, but be careful that the sun does not burn the foliage.
WATER:Water quality is very important to successful culture; always use deionised or rainwater only. Never use tap water on Disas. Always stand pots in a tray or dish of water and replace every two to three days. Never let plants dry out. In the summer months they drink a lot of water, the colder the water the better. You can add a very weak fertilizer to the water every month in summer. I never feed in the winter months, I also stop feeding when the flower spikes start to show. Many disas are lost by too much feed.
TEMPERATURE:Disas are very forgiving. They will grow in and survive hot spells of over 100 derees F, they will even take a light frost, but they do better if the temperature is cold, around 45 to 50 F minimum night temperature.
AIR:Good air circulation is beneficial to Disas. You can put them outdoors in the summer, but remember to stand in dish of rainwater.
REPOTTING:This is best done in September. Carefully remove plant from pot and wash all the old compost from the plant. Separate all offshoots, being careful not to damage the roots, then plant into clean pots one plant per pot.
COMPOST:I always use 1 part Sphagnum moss peat and 1 part perlite, and 1 part fine washed grit. You can use New Zealand Sphagnum Moss but you will have to be careful when repotting as the roots can be a job to separate from the moss without damage.
PESTS:Disas can be affected by whatever pest are present in your collection. Aphids can attack flower buds and flowers. A weak spray of Malathion will help.