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NC State Extension

Delphinium ‘Guardian Blue’

Trial: Annual

Years Trialed: 2003, 2005

Delphinium 'Guardian Blue'

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.

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.

Trial Data

Year 1

Delphinium ‘Guardian Blue’
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

Delphinium ‘Guardian Blue’
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

Page Last Updated: 8 years ago
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