Checklist for September and October

Cattleya

In spite of the shortening days and reducing angle of the sun, September can still be one of the hottest months. Water and fertilizer need to be in balance with heat and light. However, the alert grower will realize that his or her plants are starting to slow down a bit.

Any in dire need should be potted, even some that may be on the cusp, because there is just enough of the growing season left to allow the plants to establish before the days start to get extremely short and cold.

This is the month for purples come from Cattleya labiata breeding to flower. Look into this group, if you are short on flowers. There is nothing that can pretty match this type for beauty and fragrance. They are also easy to grow.

Plants spent the summer outdoors should begin to be prepared to be brought back into the winter growing area. Clean the plants up and keep a lookout for any pests they may have picked up during the summer. Then, treat as necessary.

Cycnoches

This is one under-appreciated genus. It can have both male or female flowers, and surely at its best during the autumn. Two of the outstanding varieties are Cycnoches loddigesii, with its large brown flowers similar to a prehistoric bird, and Cycnoches chlorochilon, the swan orchid. This last one has large, fragrant green flowers. The biggest problem, culturally, will be red spider mite infestations that need attention in at once. Plants are quite seasonal, needing heavy watering in the growing season and then a drier dormant winter season.

Cymbidium

Summer can be the most rewarding season for cymbidiums. Growths should be coming strong now. The foliages of the new growths are the best when they are wide and fairly stiff. The colour should be a light green to almost yellow. Early flowering varieties should be showing flower spikes, so move the plants into a cooler area with lower light. For mid-season varieties, lower the dosage of nitrogen to help in spike initiation.

Dendrobium

This is a good season for hybrids of the Dendrobium phalaenopsis and Dendrobium canaliculatum types. Both can put on tremendous shows of long-lasting flowers. Fertilize with a low-nitrogen formula to encourage the best flowers. Dendrobium phalaenopsis can get tall and top heavy, suggesting an attractive and heavy container would be suitable for this type.

Rhynchostele bictoniensis

Both Rhynchostele bictoniensis and its hybrids bloom in this season. Rhynchostele bictoniensis, formerly known as Lemboglossum, Odontoglossum) is an attractive species from Mexico that has three different color forms: sulphureum (green with white lip), album (brown with white lip) and roseum (brown with a pink lip). It is a vigorous grower with tall inflorescences of many flowers, and imparts to its offspring (as seen in Odcdm. Bittersweet and Odm. bicross) ease of culture, warmth tolerance and eye-catching patterns. They form a prime candidate for odontoglossum beginners and advanced in a similar way.

Paphiopedilumt

Standard, green-foliaged paphiopedilums begin to show their bloom sheaths this month. Late-season heat waves can destroy these early sheaths, so be observant about suitable cooling and air circulation. As with the rest of your plants that may have been spent the summer outdoors, it is time to prepare for their move inside. Clean each plant and take pest-control practices into action. Repotting is appropriate, if necessary.

Phalaenopsis

The largest part of this season’s growth is being fully developed this month, with growers in cooler weather conditions seeing the first appearing inflorescences. Some night heating may be vital in the cooler areas. Begin to watch watering more carefully, and reduce feeding proportionately with reduced watering needs. An additional dose of phosphorus and potassium, such as a bloom-booster or high-acid-type fertilizer, is beneficial.

Rossioglossum grande

Once known as Odontoglossum grande, this is a very impressive orchid with six to eight flowers up to 8 inches across. Frequently also known as the tiger orchid, it has bright golden yellow flowers heavily marked with chestnut brown barring. The plants are beautiful with a grey-green colour to the foliage, which is held on succulent pseudobulbs. It prefers hot and wet summers with cooler, even down to 40 F, dry winters. Grow under filtered light. Pay close attention for snails and slugs that eat the flowers, pseudobulbs and foliage.