In some respects, autumn is quite a busy time for the orchid hobbyist. Not quite as hectic as spring with all the repotting that most of us do but there are a lot of jobs that can help your orchids stay healthy and happy during winter.
Plants that were overlooked during spring or those that were flowering or not at the right stage can be repotted in autumn. There are some types of cattleyas that are now developing roots on new growths and this is the ideal time to repot them. Wait until you see the new roots though as there are some cattleyas that don’t grow their new roots until after flowering and repotting those orchids should be delayed until then.
Autumn is an excellent time to thoroughly clean out the growing area and get rid of weeds, sick/dead plants, accumulated debris from overturned pots and so on. If you routinely move some orchids outside in summer ensure that these plants are bug-free before returning them to winter quarters. If, as is often the case, you encounter a space crisis when trying to return the summer visitors which will inevitably have increased in size, consider donating surplus plants to the Society for prizes or put them on the sales table.
Organising the growing area
As you clean up take the opportunity to organise your plants to make care and monitoring easier. Put all the deciduous orchids and those that need a winter dormant period (i.e. those that need a winter ‘rest’) together, preferably in an area where they can’t ‘accidently’ be watered. This helps you to monitor them and to control the watering. I read about one grower who turns his resting orchid pots on their side so they can’t be overwatered. Move the high light lovers to the highest, parts of the growing area or to the aspect that gives them the best light. Make sure each plant has sufficient space so that they don’t grow asymmetrically.
For plants that have matured and are making, or about to make, inflorescences, change from a high nitrogen formula to a blossom booster type fertiliser. Keep fertiliser away from the dormant orchids and reduce fertiliser and water to the bulk of the collection, especially in cold, overcast weather.
Autumn and early winter flowering orchids
There are many cattleyas, some early cymbidiums and a host of other orchids that bring colour and perfume into the orchid house in autumn. For most of us this is a pleasant reward for our efforts over the previous growing season and a welcome change after the paucity of flowers during summer.
Autumn is the time to look out for those orchids that will be gracing the benches at the Winter Show. Start grooming plants early, and not just for the Show but also for monthly meetings.