Plant requirements

Tips For Growing Cyclamen

Susan Parent

Horticulture Specialist at Premier Tech Growers and Consumers

December 7, 2015

To successfully produce a cyclamen crop, it is all about good planning before receiving young plants. Cyclamen have a long crop cycle and, therefore, there is more time for problems to occur. Sanitation and good pest monitoring are keys to success.

*Cyclamen crop (Welby Gardens, CO). Source: Premier Tech.*

Sanitize before plants arrive

Cyclamen have a long crop cycle, so the probability of contamination is higher. Cleaning and sanitizing potting areas, tools, machinery, benches, floors and walls is strongly recommended before the crop arrives, so no indigenous disease or pests can infest the young plants when they arrive. Good sanitation should be maintained throughout the crop, to minimize disease problems.

Growing medium

It is important to use a growing medium with high air porosity when producing cyclamen. Premier Tech offers two good growing media with high air porosity, PRO-MIX HP BIOFUNGICIDE™* + MYCORRHIZAE™ and PRO-MIX HPCC MYCORRHIZAE™.

The difference is that PRO-MIX HP BIOFUNGICIDE™* + MYCORRHIZAE™ dries out more rapidly as PRO-MIX HPCC MYCORRHIZAE™ has chunk coir, which helps increase water retention.

MYCORRHIZAE™, which is found in both products, is a natural fungus that colonizes root tips and helps acquire water and nutrients for cyclamen.

The BIOFUNGICIDE™* is a natural bacterium that produces an antibody that suppresses the root disease pathogens, Fusarium, Pythium and Rhizoctonia.

Both active ingredients stay with the crop throughout the entire production cycle and are part of a good IPM program.

Arrival and planting

When young plants arrive, always store them in an isolated area to prevent any cross-contamination from areas that have not been disinfected yet. Place them in an area that has good light, but is not too intense (200 W/m²) and water lightly if needed, with no fertilizer or acidified water.

Avoid storing plants too long in their trays as this causes stretching and lower leaf loss. If plants are stretched, they will be under more stress and become more fragile, which will delay the crop. It is important to proceed rapidly and transplant into the bigger pots.

cyclamen plug trays — *These cyclamen in plug trays have been stored too long in the flat and should have been transplanted. Source: www.cyclamen.com*

Young cyclamen roots are very fragile and can be seriously damaged when transplanting. To prevent root damage, dibble a hole in the growing medium before planting, which corresponds to the size of the plug. The use of a gauge will help standardize the size and depth of the dibble hole in the pot. Furthermore, when removing the plugs from the trays, it is important to minimize handling to avoid root damage.

The bulb in the plug must be placed at the right height when transplanting into a new pot, to prevent any cultural problems. It must not be too deep, which can lead to rotting or delays in flowering and not too shallow, as this will cause drying issues. As a rule of thumb, 2/3 of the bulb should be below the growing medium surface and 1/3 above the growing medium. Keep in mind that growing media will shrink during the crop cycle, so consider this when placing the cyclamen bulb.

cyclamen bulb — *Notice the bulb at the base of this cyclamen plant. Make sure that young plants are planted at the proper depth to avoid future crop problems.*

First leaves (cotyledon)

This first leaf that was formed on the cyclamen is called the cotyledon. After a few months, new leaves will have formed on the cyclamen plant and the cotyledon is no longer needed. Often the cotyledon will dry out and eventually disappear. It is not recommended to remove this leaf, because it can cause a lesion to form on the plant and serve as an entry point for foliar disease.

Watering

Cyclamen are sensitive to overwatering and root rot. If the crop is watered with drippers, be careful not to put the pots directly on the floor, especially if the drainage on the floor is erratic or there are water puddles on the floor. Water can accumulate below the pots, wick back up through the drainage holes into the growing medium and generate irregularities in crop performance. Cyclamen that are kept too wet often get root disease that kills the plant.

Growing on the floor is also a problem if it is cold because it slows plant growth and the dry-down rate of the growing medium. There is also limited air flow around the plant canopy, unlike growing on a bench where air can circulate from under the crop. All this increases the potential for root and foliar diseases.

Sub-irrigation may be a better way to water and can reduce labor costs, but the growing medium has to be able to uniformly wick the water from one pot to the next. PRO-MIX HP BIOFUNGICIDE™ works well with sub-irrigation systems because it wicks up water quickly and uniformly. How much or how often water is applied has to be adjusted based on the weather, day length and the crop's changing needs. Ideally, excess water has to drain from the growing medium right after irrigation and must be allowed to dry out sufficiently between waterings to allow for good air porosity in the media. It is best to water frequently and with less water.

As stated, roots are sensitive to asphyxia in the growing media, so whatever method is used to irrigate, keep in mind the following:

Be sure to check under the pots after watering so that no water is standing beneath the pot.
When selecting the pots, choose those that have a spacer between the pot and the floor or table that will procure air flow below the pot.

Good drainage is important and it is crucial to check the growing medium to be sure it has sufficiently dried down before initiating irrigation. Spacing pots is also very important to maintain a good airflow in between the plants to minimize foliar diseases.