Culture Report: Mammoth and Veranda Cyclamen By Ken Harr and Kathy McKay

New breeding in cyclamen has resulted in these standout, explosive varieties.

Cyclamen have long been used as an indoor potted plant. More recently, consumers and landscapers are using this colorful yet durable plant in gardens and borders. They also make a lovely patio container planted singularly or in a combination.

Schoneveld Breeding, based in Twello, The Netherlands, offers a complete line of innovative cyclamen focusing on uniformity, central blooming, sturdy flower stems, rounded plant habit, abundant blooms and a long shelf life. Sakata Seed America is the exclusive representative of Schoneveld cyclamen genetics in NAFTA.

A popular series for 2018 is the Mammoth series. These extra large plants offer extremely large blooms on strong sturdy stems. Mammoth is well suited for gallon or 6-inch pots. The red is a true red making it ideal for holidays.

All of the Schoneveld cyclamen is bred to produce more leaves per plant. What does this mean? For every leaf, a flower is produced!

In addition, Veranda Selections, an exciting new outdoor collection, has been unveiled this year. It includes Verano (green leaf) and Picasso (silver leaf) series. Although they perform well indoors, they have also been extensively tested and proven for outstanding endurance in the landscape. The longevity and flower power produced by this collection makes it an easy choice for the home and garden.

Many times growers will focus on producing a crop as fast as possible to maximize space and reduce costs per square foot. Growing and finishing quality cyclamen is no different in that regard. The growing protocols for producing a quality crop of cyclamen can be summarized in three points:

  • Fertilizer rates
  • Moisture management
  • Disease control


When devising a fertilizer regime, it’s necessary to know and understand how well the plants can develop a good, vigorous root system. Therefore, to get the plants off to a good start — whether it’s in the plug stage or after transplanting — it is necessary to feed the plants with a calcium nitrate-based fertilizer in order to achieve a soil EC level of 0.8 to 1.0. Balanced 15-3-30, 15-3-16 or 17-5-17 fertilizers are some very good formulations to consider when deciding which fertilizer blend to utilize, ensuring there is adequate magnesium and a good minors package added in.

Once the roots are established and out to the sides and bottom of the containers, the EC levels can be lowered to 0.75 to 1.25 to maintain good, toned growth. Over-fertilization will result in plants larger than desired.


Proper irrigation levels are essential to keep the plants growing and provide adequate nutrient uptake. Because Schoneveld cyclamen have great root systems, the plants are able to readily draw up available water. However, over-saturated media can invite root rot diseases, as well as suffocate the root system. Therefore, it’s advisable to maintain a medium even moisture level at all times. Plants can be allowed to dry down slightly to maintain growth control, but the plants shouldn’t flag or wilt, resulting in plant growth that may be inhibited. Remember, it’s all about more leaf production.


Because cyclamen naturally have a dense canopy of foliage as they approach finishing, the air movement through the crop can be inhibited. Preventative fungicide applications should be applied to prevent Botrytis and other foliage and stem diseases. Additionally, Fusarium, Gloeosporium and Phytophtora can be a problem, especially in plants that are watered overhead and are exposed to splashing between plants and rows. If at all possible, it’s highly advised to place cyclamen crops on drip tubes, capillary mats or ebb-and-flow benches or floors. This will greatly alleviate the incidence of diseases throughout the crops.


Plug Stage — Germination
Maintain media pH at 5.8 to 6.0 and EC at 0.5 to 0.7. Recommended germination temperature is 62 to 64° F.

To achieve maximum germination and usable transplants, cover with medium grade vermiculite — cyclamen require darkness to germinate. Water in plug trays to moisture level 5 (saturated), then wrap the trays in poly and place them in an environment of high moisture and 100 percent humidity. Cyclamen seeds will germinate in 20 to 24 days depending on the variety.

After germination, place the plug trays in a shaded area of the greenhouse, covering with fleece and overhead misting, if possible, to prevent the media from drying out. When the cotyledon has expanded, low levels of a calcium nitrate-based fertilizer can be applied for a soil EC of .75 to 1.0. An initial fertilizer blend of nitrogen:potassium at 1:1 is recommended (during hotter times of the year it is recommended to start the plants with a 1:3 ratio and, as the climate got cooler, go to a 1:2. This will help reduce losses due to Fusarium at the end of the crop).

Transplant to Finish
Maintain media pH at 5.8 to 6.0 and EC at 0.7 to 1.0. Ideal temperature is 62 to 64° F. During warmer periods, ensure adequate air circulation over the crop and draw shade-cloths during hot periods of the day.

Transplant to finish grow time is 13 to 18 weeks depending on variety and climate. It is vital to space cyclamen on time. Optimal spacing is to place enough room so the leaves do not touch between plants.

When transplanting cyclamen plugs, the corm of the micro, mini and intermediate varieties should be placed atop the soil line. The corms of the standard and jumbo varieties should be placed slightly indented into the top of the soil line. This will ensure the emerging new root systems of the transplants grow quickly and rapidly with no setbacks due to lack of oxygen and nutrients. It is also suggested to apply a preventative fungicide, such as RootShield or Actinovate, at time of transplant. This will help with Pythium, Fusarium and Erwinia.

Following these protocols will ensure a beautiful finish to your cyclamen. With these tips and new genetics, cyclamen are a good addition to your program.

Ken Harr and Kathy McKay

Ken Harr ( is a product technical manager with Sakata Ornamentals. Kathy McKay ( is North American area manager for Schoneveld Breeding.