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Growing in the Green: Ontario container trials standouts

September 4, 2014  By Melhem Sawaya

The best growing weather in a long time was reflected in the quality of most varieties during this year’s trials season.

The best growing weather in a long time was reflected in the quality of most varieties during this year’s trials season. So when I saw a non-performing variety this season, then definitely it should never be on any retail shelf, grown in a greenhouse, distributed by a broker or even produced by the breeder.

To truly benefit from trials, we should apply what we learn from them the next season. The horticulture industry has to set a goal of making consumer success the priority. Carrying products that look good on the retail shelf, yet knowing it will not perform for the consumer, is a total disgrace and lacks integrity. This is short-sightedness because that consumer will shop somewhere else, or worse than that, will give up on gardening.


Most of the time when we go to trial gardens we look for varieties that are good performers, which is great. But what is more effective is to look for the non-performers and eliminate them from our program and send a message to the supplier.

This past spring and early summer we had many rainy days, with temperatures below average. It is amazing how fast the recovery is for some plants, and how there is virtually no setback for them at all, while others look like they went through the “heavy duty” cycle in the washing machine. These weaker varieties take five to seven days to recover, mainly from shattered flowers, with Botrytis affecting the rest if they are not deadheaded. Geranium is the first genus that comes to mind.

Many of the varieties that are not supposed to take heat very well actually performed quite well, including osteospermum and lobelia, and their flowers lasted a very long time this year.

My conclusion, which is based on my observation only, is that flower longevity is related to the average temperature – the higher the temperature, the shorter the flowering.

But if plants are outside in full sun and watered well, the flower power and strength is much better even under high temperatures.

It is still true that the higher temperature, the shorter flower life cycle – especially when light levels are low or the crop is overly shaded. That is why most of the plants, if not all of them, flower better and the flower life cycle is much longer outdoors in full sunlight than in the shade.

The main purpose of Sawaya Garden Trials is to see the varieties that perform best in our climate. Over the past 14 years, we have seen some genera perform well while others have performed poorly.

Calibrachoa, for example, has seen a thousand-fold production increase, not only in Ontario, but across Canada. This dramatic increase is due to its excellent garden performance, and the superior show it puts on from early spring to late fall, as long as we are able to fertilize on a regular basis with every watering.

Another genus that is seeing rapidly increasing production numbers is the Rieger begonia and other begonias.

In my view, ivy geranium in Ontario is a total loss as a garden performer, and we see that hardly any of the regular types were produced either. However, the interspecific varieties, such as Caliente and balcony types, are on the increase. After all, we are growing plants for the ultimate consumer, and their success is our success.

All trial plants are donated and sold locally by Norfolk General Hospital volunteers, right from the site of the trial gardens. The people that come are amazed by the quality of the plants, and are happy to pay $20 a pot for annuals even on Aug. 20!

So why are gardeners not getting the full potential beauty out of their plants?

The answer is simple; we are not communicating the information effectively to them. Unless we are planning to shrink our sales by 2.5 per cent every year, we better get together with our buyers (stores and garden centres) and representatives of the greenhouse industry and work together in educating the consumer. This is in addition to doing our homework in selecting only the best garden performance varieties.

Here are some of the steps to increase our sales:

  • Only grow the varieties that are garden-performer proven.
  • Sell the plants in larger containers than you are used to using.

As just two examples, put the flats material in much larger cells or 4”, and put 4” material into 6” pots. The rule-of-thumb is that if you have to apply growth regulators more than once to make the plant fit into the container, then it is a good indicator that the container is too small for the plant. Try this with dahlia, blue salvia, Profusion zinnias, African marigolds, and gazania, to mention a few.

  • Plant in a good potting media with no weird additives.

Delaying the watering by 12 hours or up to a day creates a false expectation with the consumer.

  • Top dressing the containers with slow-release fertilizer could be a setback for varieties that cannot take a heavy dose of fertilizer all at once, and that will happen when we get high temperatures.

All the slow-release fertilizers are released based on temperature, and it can also be affected if the plant is not being watered as required.

  • Provide liquid fertilizer free, as a bonus, when they buy your plants.

Mix it in a 200 L barrel, about a thousand times concentrated so the consumer can dilute it to end up with a fertilizer solution of about 150 ppm.

  • If we don’t do anything else, we must sell simplified drip kits so the homeowner can water his plants effectively and regularly.

If you do so, I guarantee you that plant sales will increase three to four per cent every year rather than decrease by two to three per cent if you don’t. I have first-hand experience with people who visit our trials and ask about our drip system. I tell them where to buy it and the simple steps needed to put it together. Those who do install the drip system make it a point to come back and thank me for the hint. They also tell me how they are going to buy many more plants because they know the plants are going to do very well and without any more work.

  • Get involved in advertising plants and their benefits.

In this industry, there is no sitting on the fence. If we are not part of the solution, we are part of the problem.

Looking for a winner? try ‘gardeners repeaters!’
Here are some highlights from our trials this summer. It is not very practical to try to share with you the performance of all 2,400 cultivars, so this year I decided to pick a few cultivars that were excellent performers that I will refer to as “Gardeners Repeaters” (GR).

These varieties are not in any order of importance. If you have never grown any of these varieties before, just trial them in small numbers to evaluate their success in the greenhouse and their consumer appeal. You can then decide to increase production or drop this variety. If you decide to increase production of a new variety after trialing for a season, make sure you take a good look at which variety you can drop.

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Impatiens ‘Ruffles Lavender’ (1) is a New Guinea type impatiens with some semi-double flowers. Ruffles has an upgraded look compared to other New Guinea impatiens. It has excellent garden performance and is great in hanging baskets gallons or 4” pots. Ruffles offer best value if planted in an upscale, colour-coordinated pot.

Impatiens ‘Florific White’ (2) is a New Guinea type impatiens from seed. It performed well in our trials in both shade and sun. It shows much better if grown in 4” pots instead of an 18-pack. The Florific series is worth trialing as an alternative to the walleriana impatiens.

Impatiens Big Bounce Cherry (3) Bounce Pink Flame (4) are two series that are new alternatives to Walleriana impatiens. The Big Bounce, as the series name suggests, is large and suitable for large landscapes, while the Bounce series is more compact and fits better in smaller landscapes. Both Bounces do better in the shade than the sun, not due to the sun, but more because the rain shatters the flower petals easily.

Sunpatiens ‘Vigorous Orange’ (5) is one colour in this series, as well being a compact Sunpatiens series. Sunpatiens do very well in the sun, much better than any other impatiens, and it has done very well in the shade, too, in our trials. Match the vigour to pot sizes and avoid growth regulators to get the full potential of the series. This goes for any variety, but especially with impatiens.

New Guinea Impatiens ‘Divine Cherry Red’ (6) is another seed New Guinea impatiens that is quite vigorous when compared with Bounce or Sunpatiens. Like Florific, it does better in 4” pots rather than an 18-pack. Growth regulators have a long lasting effect on it.

Begonia ‘Beauvilla Salmon’ (7), ‘Waterfalls Encanto Orange’ (8) and ‘Beaucoup Red’ (9) are three Boliviensis from three different series. The three are common in their flower power but vary in their growth habits. Beauvilla has a mounding habit, Encanto is vigorous and trailing, and Beaucoup is trailing. Grow them in hanging baskets and combinations, and in either the sun or the shade.

Dahlia ‘XXL Sunset’ (10), ‘Hypnotica Red’ (11), Dahlinova ‘Temptation Pink Bicolour’ (12) and ‘Grandahlia Orange’ (13) are samples of different sizes and shapes of this genus, which is second only to begonia in sales growth. They do well in the shade but excel in the sun whether in containers or beds. Grow them in suitable pot sizes to match the growth habit of the cultivar. Dahlia flowers the whole summer long.

Isotoma ‘Laurentia Blue’ (14) features star-shaped flowers on an upright plant habit that is distinctive. It has an excellent growing habit the entire summer. No deadheading is required. It is easy to care for and is as great in the garden as it is in containers.

Ornamental Millet ‘Purple Baron’ and ‘Jade Princess’ (15) are not new, but are great performers. The ‘Baron’ is much taller than the ‘Princess,’ so growth regulator treatments differ. Both are excellent centres in combinations, especially in fall planters; birds will be especially thankful for the ‘Baron’s’ plentiful food bank of millet seeds.

Mandevilla ‘Sunparasol Red’ (16), Dipladenia ‘Rio White’ (17),  and Dipladenia ‘Rio Red’ (18) are my number one GR plants due to their performance that includes continuous flowering and resilient growth habit. These are not shade plants if flowers are the desired, and the warmer the temperature, the better the performance. They are upscale plants sold at premium prices.

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Gaura ‘Stratosphere White’ (19) is a great performer. Gaura has been the most attractive and popular plant at trials the past 10 years or so, but it does not sell well in garden centres. It’s because gaura does not fully impress unless it is displayed in large groupings either in mass plantings or with five to six plants in large pots, and that is because of its airy character.

Rudbeckia ‘Tiger Eye Gold’ (20) is an annual plant that competes with any other plant in flowering power and performance. Tiger Eye flowers the whole season until well past the first mild frosts. It is an excellent late spring plant, and also works well for fall sales in combinations.

Heliopsis ‘Tuscan Sun’ (21) is a great late-spring plant that flowers constantly. Like other perennials, the plant will be bigger the next season and will have a much larger show of flowers. ‘Tuscan Sun’ puts on a great show the whole summer long and it is a GR for me because it is going to survive in your garden for many years.

Incarvillea ‘Cheron Pink’ (22) is an airy flowering plant that starts slow but then sprints into the most graceful plant around. Incarvillea is great in large pots and mass plantings. It is a must, especially for garden centres.

Nemesia ‘Sunsatia Lemon’ (23) is quite impressive. I think we finally have virus-free nemesias that flower the whole time – winter, spring or summer. Sunsatia has great flower power with blooms that last a long time. It is excellent in landscapes, large containers and combinations.

Begonia ‘Solenia Light Pink’ (24) is one colour in a series that does well in the shade but excels in the sun. Solenias are great in full sunlight the whole summer with excellent flower power on sturdy plants.

Pansy ‘Cool Wave Blue Berry Swirl’ (25) is a great summer performer. I never thought that I would be saying that about a pansy. Cool Wave pansy has a long season since it blooms in cool temperatures and excels through the summer. Cool Waves pansy are not just for spring sales. They are great as hanging baskets alone or in combinations.

Zinnia ‘Profusion Yellow’ (26) is one of the colours in this series that puts on an excellent show every summer. This low input cost material has a short growing time, and it gives gardeners total enjoyment the whole summer.

Lobularia ‘Shimmer Pink’ (27) is a cool weather crop that is also especially  hot in the summer. It’s much like the Cool Wave pansies – a three-season sales item that is great in hanging baskets and landscapes.

‘Enduro Lavender’ (28) holds its flowers longer than most other verbenas, which makes it a breakthrough in verbena breeding. This makes Enduro a viable plant in combinations without having the agony of deadheading it even in the greenhouse like many of the other verbenas.

‘Superbells Lilac’ (29) and ‘Mini Famous Double Pink Vein’ (30) are only two of the many excellent calibrachoa varieties on the market. These two varieties show the diversity in this genera and breeding efforts to get that unique flower on a good performing plant. You can find calibrachoa in all sizes, and from very compact to quite vigorous, and all with a good selection of flower colours. Calibrachoa is great in landscapes, hanging baskets and in combination with other genera and other cultivars of the same genera.

Petunia ‘Supertunia Vista Bubblegum’ (31) has been the champion variety of our trials for the last five years or more. I call it the plant that never stops giving. The Vista series, and especially ‘Bubblegum,’ is great at the beginning of the season and they get better from then on regardless of hot or rainy weather. It is the best plant, period. No wonder that you see them in most downtown hanging baskets.

Lantana ‘Bandana Trailing Gold’ (32) has great summer performance. It performs well in rainy weather but excels in hot, dry summers. Lantana make excellent hanging baskets or upright containers, and are great in landscapes. Lantana should be sold in late spring to show its full potential at sales time.

‘Master Idol Flame’ (33) is a robust geranium variety in a great series known for garden performance in hanging baskets, combinations or landscape.

Bougainvillea ‘Razzle Dazzle’ (34) is a different flowering plant and stands alone as a high-end quality plant. For the last four years, we had the bougainvilleas in our trials and to my surprise they flower the whole summer long. The dense clusters of florets last for a very long time, allowing more than enough time for other branches to set buds and flower. Bougainvilleas are excellent in large containers the whole summer long. It definitely makes the GR list, especially with its wider selection of colours.

The trial pictures will be posted on my website at Any Questions or comments are welcomed to:

WELCOMING special guests THIS YEAR
About a dozen members of the Garden Writers Association were welcomed to a special day at this year’s Trials. (35)

The writers, who have their own blogs or contribute stories to consumer magazines and newspapers, came from throughout southwestern Ontario.

It’s the first year for this open house for GWA members, and they were quite enthusiastic with the tour of some 2,200 cultivars. Most said they’d be back next year and would be spreading the word with other GWA members.

The chance to see this year’s trials standouts, and probably next year’s gardening star performers, on one day and in one location was roundly welcomed by the guests.

I outlined how the trials have grown over the years, and how the containers are maintained throughout the season. (36)

Melhem Sawaya of Focus Greenhouse Management is a consultant and research coordinator to the horticultural industry. Comments on this or any other article are welcome at:

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