Hi, I've been growing a small handful of dahlias (typically 4-5 cultivars, now 7) for a bit over 5 years now and I'm thinking it's time to be a bit more serious, so I'm looking for good source material. An authoritative reference on my bookshelf could be nice - I looked into what's available in Amazon, and it seems we have 3 similar books - all of them were last published during the earlier years of the last decade, most of these seem to be written for both North American and European folks (McClaren seems to target only Americans), and the major difference besides that seems to be how many pages they devote to dahlia care vs. listing different cultivars.
Encyclopedia of Dahlias [Paperback] Bill McClaren - 212pages
56 GBPThe Gardener's Guide to Growing Dahlias Gareth Rowlands Paperback: 160 pages
40 GBPDahlias: A Colour Guide Ted Collins Hardcover: 240 pages
20 GBPEurope and North America differ greatly in the selection of cultivars and the dominant classification system (NDS of UK vs ADS). It seems that the leading dahlia nations on our side of the pond are UK and the Netherlands, there's big online shops in both places that offer hundreds of cultivars and they are of course within the sphere of influence of NDS, so it makes sense for us Europeans to mostly pay attention to their classification system.
Any book you'd recommend or avoid?
BTW I live near the Southern coast of Finland, dahlias grow nicely here and reward you with months of beautiful flowers :) I hear there's some people who even grow them in the Northern parts of the country.
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