Another easy to grow group, Vandas and Ascocendas are the sun loving relative of Phalaenopsis, enjoying similar conditions but requiring a lot more light.

They originate from Central Asia and can be found in India, Nepal, Indonesia, Thailand, Burma, China, New Guinea and the Philippines where they climb up trees as they grow using their strong aerial roots to support them.  Some varieties prefer hot, humid environments and some prefer the conditions high up in mountains, (up to 1,200 meters).

The plants are made up of a thick, fleshy, upright stem with stiff strap-like leaves that grow from the tip of the plant, alternating on opposite sides of the stem.  The thick, silvery aerial roots are produced at intervals along the stem usually opposite a leaf.  Food and moisture are retained in the leaves and roots.  Flowers develop on short stems between the leaves usually near the top of the plant. Individual flowers should last 3 to 6 weeks.

In there native habitat they are epiphytes which means they cling onto plants or rocks rather than grow in soil – They are NOT parasites.  Vanda are sold by Ivens Orchids in clear plastic pots, allowing light to get to their roots, and are potted in large grade orchid compost that is very free draining, allows plenty of air to the roots and does not breakdown too quickly.  Vanda can also be purchased, (from other suppliers,) supported on bark, in glass bowls or hung up in open baskets. (In pots, plants are more manageable and require less watering than when the roots are exposed where they will need regular daily watering or misting.) 

Temperature:  Vandas require a constant warm environment making them a good plant for the house.  A minimum nighttime temperature of 16-18°C and a daytime temperature of 18-24°C are ideal.  But mature established plants would be able to cope with temperatures as low as 13°C and all plants should be able to cope with temperatures as high as 32°C for short periods.

During the winter, plants may appear to stop growing and the plant may go into a period of rest.  It is possible to keep them a little cooler at this time, but since most homes are centrally heated the temperatures will probably stay warm enough for the plants to continue growing.  Plants that are allowed to cool to below 10°C for any length of time may go in to a dormant state for self protection.

Light:  Vanda are sun loving plants requiring good light levels, even direct sun, although care should be taken to shade them from the scorching conditions of the full midday sun of high summer.  They will be happy on a very sunny windowsill or conservatory with high light levels.

Water:  It is important to take care and water your plant correctly.  Never over water or allow the plant to become waterlogged.  The roots are extremely vulnerable to over-watering when potted.

As a general rule, soak the roots well and then leave them to dry until they go silvery before watering them again.  In dull, overcast conditions, water less frequently.  Vanda, as with most orchids, do not like to stand in water.  Always water well from the top of the pot and allow excess water to drain away.  Dunking the pot in water is an acceptable way of watering. 

Exposed roots on plants hanging from bark or baskets should be misted regularly once or twice a day depending on conditions.  Do not "part water" roots; i.e. always soak roots fully.  Roots outside the pot and leaves can be misted once a day.

Clean rainwater is preferred by the plant but you can use filtered tap water.  Try to water with tepid or room temperature water.  [Tip:  Leaves can grow too vigorously at the expense of flowers if the plant is kept too well watered and not given sufficient light.] 

NOTE:  NEVER STAND THE PLANT IN WATER OR ALLOW THE PLANT TO BECOME WATERLOGGED.  This will cause the roots to rot and kill the plant.

Feed:  Feed regularly, every second or third watering with a balanced orchid feed, such as Ivens Orchids’ Orchid Feed, throughout the year, although it is not necessary to feed the plant if light levels are low.  If the plant looks like it is not growing it may be in a rest period or dormant when feeding can be withheld for a month or two.  Do not be tempted to use a strong solution of feed; little and often is best.  The plants will also benefit from an occasional flushing through of fresh water to remove any accumulating salts from the compost.

Air Humidity:  Good ventilation (not drafts) and moist air is essential.  The humidity can be raised by placing the plant on a tray of moist gravel or pebbles.  50-80% humidity is ideal.  Vanda can be lightly misted to help maintain high humidity; this is best done in the morning.

Spring into summer is the main growth period for Vandas; ventilation is very important at this time. If they get very hot during the summer it is advisable to increase ventilation to allow for the leaves to cool down, but high humidity is also important especially when the temperatures are high.

After Flowering:  Cut the old flowering stems off when the flowers are over and this will encourage the plant to produce new flower spikes from higher up the plant. 

Note: Some Vanda species flower once a year and some varieties can flower several times a year.

Repotting:  Vandas do not like to be repotted and should only be repotted when compost starts to deteriorate; as a guide, large bark deteriorates after about three years.  Repotting should be carried out after flowering and when the new roots develop, ideally during the spring and early summer.  It is not always necessary to pot on to a larger pot, in fact, most of the time you are only replenishing the compost and the plant will happily stay in the same size pot for many years.  Only use a larger pot if it’s impossible to get your plant back into its pot.  Care should be taken not to damage the healthy roots, take great care not to damage new growths wherever possible.  Large clear pots are available from Ivens Orchids.  Use good quality orchid bark, such as Ivens Orchids’ General Purpose compost.  

Basic Repotting Technique:  Tap the plant out of its old pot and inspect the condition of the root-ball.  Try to disturb roots as little as possible.  Remove old compost and all the dead, soft or black roots.  Using a clean clear pot, support the plant in the centre of the pot while you feed fresh orchid bark around the root-ball; tap the pot gently as you continue to feed in bark and ease it between the roots.  Do not pack the bark in too firmly as these plants prefer a free draining pot with a good supply of air.  Always dampen down the bark before potting and only water sparingly for the first 2 weeks after repotting or until you can see new root growth.

Pests:  Prevention is always better than cure so look for good, healthy plants to start with and keep them that way with a clean environment for your plants.  Throw away old, weak or infested houseplants and maintain good housekeeping in the greenhouse.  Most often seen pests are scale insect, thrip, red spider mite and mealy bug.  They will weaken the plant if left unchecked but, if found early enough, they may be cleaned off with soapy water or a cotton bud dipped in a small amount of methylated spirits; otherwise treat with a specific systemic insecticide.

Buying Tips:  Always buy good quality orchids from a reputable supplier and look for clean healthy plants.  If buying plants in flower, check the flowers are not damaged or that the pollen caps are still on the flowers.  If these get knocked off by poor handling or contaminated by poor storage or transport conditions the flowers will very quickly discolour or “go over”.  Unless you have ideal transportation and growing conditions, buying a plant with immature buds may be a mistake as some plants can be sensitive to being moved during the early stages of flower development.  Look for plants with flowers already open or buds that look quite plump and ready to open.  Don’t be afraid to buy a plant whose flowers are nearly all out.  Vanda flowers grow larger as they develop. 

Handy Hints:  Keep your plants clean and healthy by occasionally cleaning the leaves with a mixture of 1 tablespoon of olive oil and a few drops of washing up liquid mixed in warm water.  Using a sponge cloth, wipe over the leaves with the mixture. 

Special Notes:  Sometimes plantlets, (Keikis,) develop from the base of the plant or between lower leaves.  Allow these to develop a few roots then you can remove them from the parent plant and pot them up.

If a lot of leaves fall off at the base of the plant, (this can happen with a mature plant,) or if the plant gets too tall, it is possible to cut off the lower part of the stem and retain only the top growth.  Cut through the stem just below a strong aerial root and repot the top younger section into fresh medium, (see Repotting above).