Greenhouse Canada

Features Crop Culture Inputs

November 11, 2008  By Melhem Sawaya

It is hard to believe that what started out eight years ago as a 150-variety vegetative trial now encompasses 2,000 varieties. What is more surprising is that those previously mentioned 150 varieties covered 95 per cent of the vegetative varieties on the market at that time

 “Welcome to the eighth annual Sawaya Garden Trials.”

Sawaya Garden Trials offers plant enthusiasts the chance to compare market leaders and newcomers

It is hard to believe that what started out eight years ago as a 150-variety vegetative trial now encompasses 2,000 varieties. What is more surprising is that those previously mentioned 150 varieties covered 95 per cent of the vegetative varieties on the market at that time. Now, the 2,000 varieties also represent about 95 per cent of the vegetative varieties on the market, an increase of 1,333 per cent. The increase in consumer demand and the increase in varieties fuelled the market, resulting in a major increase in sales.


Large container sales and vegetative potted plant sales increased by 1,000 per cent over the past five years, while at the same time bedding plant flats decreased by more than 60 per cent. With the increase in the large containers that have new vegetative material and good variety performers, the need for greenhouse trials and field trials is an essential ingredient to the continuous increase in sales of this sector.

For a trial to be beneficial for the whole industry (consumers, growers, brokers and breeders), certain procedures have to be followed without deviation.

The whole range of available varieties has to be at a trial and not just selected items. What the breeder/broker/grower wants to sell is not necessarily what the consumer wants. So a trial of the whole range gives consumers, buyers, breeders and growers a better idea of cultivars that are more in demand and will translate into increased sales.

Display gardens that represent one line are only beneficial for half the equation that will promote the breeder’s line and that of the broker, but it cannot give a true picture for the grower on which varieties to grow, and more importantly, it will never ultimately tell the consumer which cultivars will perform well in their own gardens. Good plant performances at the consumer level will definitely increase sales because they will buy more.

However, plants that don’t perform well at the consumer level will create less sales in the long term, because no one wants to waste their money on a commodity that gives little to no enjoyment.

Breeders/brokers that are trying to create programs for the chain buyers defeat the purpose when their only interest is to sell their own varieties, whether they are good or not. More importantly, when these varieties are not put through the test of greenhouse production, consumer appeal and garden performance trials, the result is a diminishing of any increase in the horticultural industry.

Programs for the introduction of new varieties should be in place and be honoured by the breeder, broker, buyer and grower in greenhouse trials and field trials.

This year, another factor was added to the trials that was not planned. Three days after we put the plants on the stands, a hail storm that lasted 10 minutes shredded most of them. The only species that was hardly damaged were the Calibrachoas due to their flexible growth habit and small leaves.

We learned a few extra aspects from the storm:

1.    If you pinch Osteospermum in the summer, it will flower seven weeks after.

2.    Almost every plant became bushier than normal.

3.    Plants looked fresher later in the summer than usual.

4.    If this is to happen again, or we pinch the whole crop, water management is critical. Light waterings are needed; never over-water until the foliage canopy grows again.

5.    We might take this as procedure and, next summer, pinch most of the crop around June 20th.

6.    Things always work out for a better reason.

It is very hard to provide an overview of 2,000 different cultivars in an article, but here are some highlights.


We had more mix containers this year than other years, and next year we are planning to add even more. It is one thing for a mix container to look nice in a greenhouse, but it is more important to look nice for the rest of the summer! This Angelonia, with white Impatiens and Red Star spike, (1) looked nice the whole summer, especially when it was placed on a stand in the middle of a flower bed of the same combination. 

Vegetables are having a comeback. This past season, many customers were interested in large pots of vegetables in 4” and 6” pots. So we took this to the next step and sampled some vegetables in 14” pots, like this pepper (2) and the ‘Tumbling Tom’ tomato (3). Some vegetables looked good and they were easy to take care of, like these two pots – especially the Tumbling Tom tomato, from which we enjoyed over 450 little tomatoes from a single pot throughout the summer season.

One of the oldest genera of plants is the Geranium, which still accounts for a large portion of the bedding plant crop. Breeding is still after a new, improved characteristic of a vivid colour like the new Calliope (4), which is an interspecific with an Ivy Geranium to get a very nice red bloom. This picture doesn’t do this variety any justice because of the extremely heavy and frequent rain that we had this summer. This kept any Geranium flower from looking its best, which is the downside of geraniums in general. Also, the frequent rain leads to a continuous job of dead-heading the dead or semi-dead blooms for looks and to prevent botrytis-infected blooms from spreading all over the plant.

Also, Geranium breeding is after a more vigorous dark leaf geranium like the ‘Savannah Pink Sizzle’ (5), an excellent variety for large patio pots of geraniums or geranium combinations.

Breeding has come a long way, especially with varieties that couldn’t handle the summer heat, including Lobelia, Nemesia, Diascia and Osteospermum.

Lobelia ‘Techno Heat Dark Blue’ (6) and Lobelia ‘Waterfall Light Lavender’ (7) bloomed the whole summer in full sun. Their blooms are resistant to frequent rains and the new flowers always covered the spent ones. So by using these varieties alone or in combinations, the consumers can enjoy them the whole summer long.

‘Nemesia Nemo Deep Blue’ (8) is another example of the advanced breeding of Nemesias that bloom all summer long and even look better as the summer goes on.

‘Diascia Darla Deep Salmon’ (9) and ‘Diascia Flying Colours Coral’ (10) also put on an excellent show, with outstanding bloom retention and healthy foliage. The advantage of these cool crops – the Lobelia, Nemesia and Diascia – is that they can be sold as a cool crop in late April and the consumer can enjoy them, not just for April and May, but all summer long from April until past frost in October in Ontario’s climate.


Another species that fits into this group is the colourful Osteospermum. The days of Osteospermum of different shades only of blue are gone and now we have Osteospermum in all colours that put on a show a consumer cannot resist. Examples of these cultivars are ‘Osteospermum Zion Pink Sand’ (11), ‘Osteospermum Flower Power Ivory’ (12) and ‘Osteospermum Maria White’ (13). Osteospermum can be sold in 4”, 6”, and now in large 12” and 14” containers as stand-alone or combinations and will give the consumer the longest season of enjoyment since it can take mild frost and not only withstand hot weather but flourish in it.

Now we take you from the cool-tolerating crops to the heat-loving plants that seem to say “thank you” for every day the temperature is above 30ºC, or at least above 25ºC. Angelonia, or as it’s commonly called ‘Summer Snapdragon,’ loves the heat. Even without dead-heading, the May bloom still looks good when the September bloom comes out, which is excellent for late May or June sales.

‘Angelonia Angelmist Lavender Stripe’ (14), which is started from cuttings, and ‘Angelonia Serena Lavender Pink’ (15), which is from seed, are examples of the excellent performance of Angelonias.

Bracteantha, or ‘Straw Flowers,’ had a setback three years ago when cuttings came with downy mildew and the plants fell apart before getting to the consumer because we put too many cuttings per container. It seems that, over the past two years, the stock producers have taken care of the downy mildew problem and we learned to put only one cutting in a 6” pot; with some varieties, we could use only one cutting to make a 10” hanging basket, on its own or with a couple of fillers. ‘Bracteantha Mohave Yellow’ (16) is an example of the new Bracteantha breeding. Also, the extremely long-lasting characteristic of the Bracteantha bloom is very unique and advantageous since the plant blooms for a wide sale window.

The mother of the vegetative flower mania is the Scaveola and, even though only a few colours are available, it is still the most durable genus of all vegetative plants, can take the cold, loves the heat, and no dead-heading. ‘Scaveola Fancy Blue’ (17) is an example of excellent plant habits.

Petunia is the largest genera in the vegetative flowers. From the seed Petunia comes the first Wave Petunia, which is a landmark for all other Petunias. A landmark not just for its quality but for its deserving of a Nobel Prize for the best horticulture product ever marketed because of its diversity as a single flower large, single flower small, large double flower, small double flower, Petunias that can trail up to eight feet and, colours that exceed those of the rainbow. Petunia can be part of any mix, alone in every container size, for early sales and also summer sales.

‘Petunia Supertunia Mini Blue Veined’ (18) is an example of a small flower that covers the entire plant canopy. ‘Petunia Supertunia Vista Silver Berry’ (19) is the landscape Petunia that is still underused but, once a consumer tries Vista, then it will be a highlight in their garden every year. For a higher-end look, ‘Petunia Doublewave Blue Vein’ (20) is an excellent item, especially in combinations.

Calibrachoa has all the characteristics of Petunia with the advantage of blooming in a lower light level, and rain does not affect the blooms. In our trials, Calibrachoa plants and blooms looked fresh 30 minutes to one hour after a heavy rain.


Here are just a few examples of the many Calibrachoas: ‘Calibrachoa Mini Famous Compact Orange’ (21); ‘Calibrachoa Superbells Peach’ (22); ‘Calibrachoa Million Bells Chiffon’ (23); and ‘Calibrachoa Celebration Double Pink’ (24).

In the January 2009 issue of Greenhouse Canada, I will be writing an article on Calibrachoa production, varieties and use. Calibrachoa is the fastest growing species for the last three years. I wouldn’t be surprised if Calibrachoa surpasses New Guinea Impatiens in two years!

Next month we’ll continue our Trials overview with our discussion of the Top 10 varieties.

The Sawaya Garden Trials are designed to fill the gap between the consumer and the breeder by not ignoring any factor of the trialling process. The majority of the breeders, brokers, store buyers, growers and consumers are all part of the process in increasing the awareness of gardening enjoyment, which will result in greater success for everyone.

The success of the Sawaya Garden Trials is only possible with the help of many participants: Allcover Portable Systems, Greenhouse Canada, JVK, Ball Superior, Yoder, George Sant and Sons, Linwell Gardens, Ed Sobkowich Greenhouse, Greenfield, Northern Innovators, CF Greenhouses, Creekside Greenhouses, Dosatron International, Vanderhoven Greenhouses, MacGregor, Plant Products, Specialties Robert Legault, Sonnyside Flowers, Vacform/Concept Plastic, C. Frensch Ltd., VRE, ITML and Vandenbush Irrigation. These are in addition to all the breeders and trademark companies, namely Ball Flora Plants, Simply Beautiful, Proven Winners, Flower Fields by Ecke, First Class, Fides North America, Sakata, PanAm, Bodgers, S&G, Syngenta, Goldsmith, Garden Performer, Natural Selection, Oglevee, Takii, Dummen, Danziger and Suntory.

With a 2,000-plus plant trial, the different flower colour, leaf shapes, textures and plant habit will give any person visiting the trial a sense of amazement of the huge versatility of garden plants. At the same time, it will only take the imagination of the grower to come up with a product mix that is unique for their operation and, most likely, not duplicated by every grower. If a grower depends on a sales person to do their product mix, the chances are that a number of growers will have the same product mix and that will take away the advantage of uniqueness.

Melhem Sawaya of Focus Greenhouse Management is a consultant and research coordinator to the horticultural industry. Comments on this or any other article are always welcome, please e-mail

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