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Report From
by Terry Dowdeswell
January 1, 2000

Looking past the computer screen and through our office window to the warm rain falling outside, straight down in large, heavy drops I can just about hear the powdery mildew action committee drawing up plans for attacking our delphinium plants. Well keep out, stay off, and go find a few courgettes or something will you!

Ok, so the winter has taken away your garden (just minding it for a while) and folk in the cold north are dreaming of warm sunny days. Like to take a look out of our window right now? Summer's here but hey, we don't get a break from a growing season save for a couple of months when things slow down a little, so you relax while you can, enjoy the view and let us do the hard work, stoking the bar-b-que, entertaining friends on the lawn, eating the fresh veggies. Only made you envious? Well too bad, you can come and help us weed sometime!

Janice and I recently shifted our delphinium breeding business (New Millennium Delphiniums) about 300 miles south to Wanganui, New Zealand and are experiencing our first summer here and yes, it's warm and humid and powdery mildew is threatening. Fortunately it is very selective, mainly attacking purple shades and some creams so these colours generally give an advance warning and remind me do get the sulphur out and try to keep the air moving.

Air moving? Of course moving the air outside is a tad difficult and helicopters do come on the expensive side in Wanganui. That's why we grow our seed crop inside (much less air to move) and one of the advantages of our new location is that generally the air is quite capable of moving its self outside anyway. In fact it can move its self fairly sharpish at times, but I digress. Pollination in the plastic growing house is now well under way. The English hybrid type delphiniums we breed tend to resist powdery mildew a little more than say, Pacific Giants do. Every little helps.

Growing our delphiniums under plastic gives more heat and a higher humidity. This is good for seed setting but rather hard on the plants. Again there is a good side. Growing delphinium in 25 to 30degC (80 ­ 90degF) temperatures naturally selects for plants that generally tolerate these conditions and this is indeed one of our aims. It is also useful to receive reports from customers in Canada, USA and Europe who tell us their frost hardiness is still very good too.

From time to time articles in the English "Delphinium Society Year Book" (an excellent publication) refer to a delphinium cultivar producing different shades of colour according to, presumably, the soil and climate in which they are grown. We heartily concur. The move south has resulted in a general enrichment of flower colour and some paler, or mottled varieties appear a little different. While on colour, pink delphiniums lose their "pinkness" quickly in high light conditions. Try planting pinks in front of grey foliage plants (eg. artemisia) and in areas that are shielded from the fiercest of the sun's rays such as near a loose leafed tree to the north. Of course if you have a loose leafed grey/purple tree like an Acacia purpurea (Wattles may not be hardy for you) you have the best of both worlds. We are developing delphinium display gardens over the next few years and will post pictures of such things on our web site at where you can also find cultural information and the invidious, but necessary order form which I wont mention.

Terry Dowdeswell
1570 Brunswick Road
New Zealand

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