Delphinium ‘Guardian Blue’
go.ncsu.edu/readext?225676
Trial: Annual
Years Trialed: 2003, 2005
Good Qualities
Year 1
Nice iridescent purple-blue color (7); Strong stems (3); This color delphinium stole the show every week!, intense blue with lavender shading was vibrant and beautiful, I sold every stem of this every single week, this will replace Bluebird in my future plantings; Strong stems; Flower stems are full and very well accepted; Good for everyday design; Large flower; Great plant, nice stem length; Plant forms a healthy rosette; Very happy to get bloom in same season; Plants grew vigorously and weren’t reluctant to bloom well in the first season.
Year 2
Bright blue flowers (4); Long stems (2); Very tall stems; Much desired by florists and market customers; We really like the Guardian series and have them planted; Very uniform; Fast, good germination, big enough stems; Strong stems, good plant size.
Problems
Year 1
Poor germination (3); Short for delphiniums but expect it to be taller next year; Lost several transplants to cold after planting to field, stems could be longer; We stratified the seed on all delphiniums for 4 weeks prior to setting out in the greenhouse; Plants and stems never grew very tall, maybe because of weather and fertility; Lost too many in plug trays; Started too late, no blooms; Some mildew as the crop aged; Needs a cooler, earlier start than I can give it, only time will tell if plants set out this fall will be productive next spring.
Year 2
Heat in Texas can be too much!; Florists like more length; This particular ‘Guardian’ did not germinate well, or thrive – especially compared to the other 2 trial varieties and also the ‘Guardian’ we had in our main cutting area, not really sure what the issue was; Individual flowers very large (almost too large for design) for length of stem; We would have had better luck with this in the fall.
Postharvest
Year 2
Change water every day. See separate postharvest report in this issue for results from NC State University postharvest evaluations.
Trial Data
Year 1
| Yield (stems/plant) | Stem Length (inches) | Market Appreciation Rating¹ | Repeat Again Rating¹ | Ease of Cultivation Rating¹ | Average Spacing (in2) | |||
|---|---|---|---|---|---|---|---|---|
| Wholesale | Retail | Consumer | ||||||
| Average | 2.6 | 25.3 | 4.0 | 3.7 | 4.3 | 4.2 | 4.0 | 124 |
| Range of Responses | 1-8 | 17-36 | 4 | 2-5 | 2-5 | 1-5 | 3-5 | 36-216 |
Year 2
| Yield (stems/plant) | Stem Length (inches) | Market Appreciation Rating¹ | Repeat Again Rating¹ | Ease of Cultivation Rating¹ | Average Spacing (in2) | Average Postharvest Life (days) | |||
|---|---|---|---|---|---|---|---|---|---|
| Wholesale | Retail | Consumer | |||||||
| Average | 3.7 | 23.8 | – | 4.3 | 4.0 | 3.9 | 3.4 | 130 | 6.0 |
| Range of Responses | 1-12 | 18-40 | – | 4-5 | 3-5 | 3-5 | 2-5 | 36-324 | 5-7 |
¹1 to 5 scale, with 5 being the best. Market ratings are based on sales to wholesalers, retailers, or final consumers direct.
Supplier
PanAmerican Seed
P.O. Box 438
West Chicago, IL 60186
Comments
Year 1
Similar to ‘Magic Fountain’; We mainly grow ‘Oriental Blue’; ‘Guardian’ is a nice color and more like standard delphiniums, it will be a nice addition if it overwinters and is not too tall; We have had numerous frosts and the plants are still blooming and beautiful, flowers once cut, lasted well; Might do better in hoophouse or field in cooler weather, on 10/24, plants look healthy and some have new flower stalks with flowers about to open, but they are short (Zone 7); For first year I think it did quite well; I think I’ll like the ‘Aurora’ series better; I personally prefer to buy plugs for delphinium.
Year 2
Seeded in flats on 5/05, gave 2 weeks cold treatment, only 12 transplanted to field, harvest interval 6/29 – 8/31; First bloom August 25 (Zone 2), will look for taller stems next year; Have had other ‘Guardian’ colors in the past and like the variety very much – seems to winter over well here in Michigan.