When I got my tubers in from Swan Island this year, and read their catalog's instructions on how to grow them, they once again said that dahlias need AT LEAST 8 hours of full sun, or they will not flower well if at all.

Then I called Swan Island to ask a question, and while I had the lady on the phone(who didnt seem to want to be bothered with any questions), I asked her if less than 8 hours of full sun would be enough, and she very sternly reiterated that dahlias need AT LEAST 8 hours if not more!

The reason I was concerned is that we live on a 1.25 acre, heavily wooded lot with only 2 clearings that get limited sun. But if we move from one spot in the clearing to another spot just 10 feet away, the amount of sunlight in the new spot drops about 1.5 -2 hours per day. So we cannot just grow in any spot in the clearing.

The area where I grew my large Dahlias and large Zinnias is the sunniest spot, in that it gets about 6-8 hours of sun in high June, depending upon which area within that spot we planted. The dahlia at the top of the rows gets 7.5 - 8 hours in June, and the Dahlia at the bottom of the rows just 9 feet away gets 6 hours. But as the months go by, and we get into sept and October(prime Dahlia blooming months), the amount of daily sun is down to like 2-4 hours per day, or less! Then by late October, none are getting more than 1.5 - 2.5 hours per day.

I planted later than I wanted too. Half were planted as dormant tubers on May 25, and the other half as dormant tubers on June 11. So they were just starting to come up at the height of the summer solstice, when they were getting the most sun they'd get all season. From there on, the sun began to sink down in the sky(beginning in mid July or so).

However, the only problem I seemed to have related to lack of sun was the fact that all but 1 plant grew taller than advertised. They were supposed to be all 4 feet tall, with only 1 plant, Vassio Meggos at 4.5 feet tall.

Well, most grew between 5 - 6.5 feet tall, with Vassio Meggos growing it's tallest flowers almost 8 feet tall!

But, I pruned them all at the 3rd leaf level initially, and they ALL grew nice, thick, healty, strong stems, which were only trellised by the upside down tomato cages which were only 30" tall, so the top 2/3 of each plant really didnt need trellising, except for during 2 hurricanes when I temporarily tied the stems together so they wouldnt blow around too much.

But as far as flower productivity, they were GREAT! In fact, most of them became most productive later in the season, once the amount of sun had plummeted, and half were producing a glut of flowers in mid-late October!

Out of only 6 large dahlia plants and 2 smaller ones, we were swamped with cut flowers from my dahlias to the point where I had at least 15-40 flowers inside in vases at any given time once flowering, and I was also constantly giving bunches away to friends, family and customers as well!

So, I question the claim that dahlias need AT LEAST 8 hours of sun or more or they wont flower well at all......

Keri~

It seems that a lack of sun will make many plants grow tall...

However, my tomatoes also grew tall due to lack of sun, but their stems were pencil thin, and wanted to fall over, but my dahlias were thick, strong and healthy, and need very little support.

They also bloomed VERY well even though they didnt get the 8+ hours of sun they allegedly desperately needed.