I have a weigela that requires full sun. I want to plant it in front of my house. The place it will be is on the northern side. The spot gets sun from the west from about 3:30 until sunset. Do you think that's enough?
Maybe. I've found most weigelas are somewhat more tolerant of shade than one would expect. I have "carnival" literally under an oak (that was an accident!) getting about 4 hours of west sun, and it blooms profusely, however it has grown to less than half the expected size. Another weigela is on the north side of a large shed but beside pine trees, and while it is slow to fill out, it is now full-sized and blooms as expected - note that it has morning shade, but full sun from noonish on. Still another one is on the south side, close to the house and *that* one puts on a fantastic show every spring. I'm inclined to think that having a 'sweet' soil is important, and that your weigela will bloom nicely as long as it gets at least 6 hours of direct sun.
BTW, "full sun" is usually meant to indicate a minimum of 8 hours of direct sunlight.
full sun is a minimum of 6 hours in most of the country.
and 'quality of light' is also an issue here- four hours between 11 am and 3 PM give much more light than 4 hours outside those times.
a northern exposure will never have full sun in this hemisphere.
it may survive, but it will likely not flower. you would be better off with something like coral bells (which have burgundy foliage) or a shade-loving shrub.
Since this question has been asked I would like to add the question of what time of year are these 6 hours of sun needed? Because as the seasons change so does the light in my yard.
I don't think that location is a good one for your weigela. It's probably not enough to maintain a good foliage color, if you have one of the burgundy plants, and I doubt that it will flower well. Think about it: the sun sets awfully early in the winter!
Though I agree with Meldy about this plant doing just fine with 6 hours (maybe less), I think you'll be pushing it a bit in this location. It does not even remotely qualify as 'full sun', by any stretch of the terminology.
Well after reading all of your responses, it looks like my front bed just isn't going to cut it. I really want this plant though so I've decided to move it to my island bed. It's still on the north side of my house, but it is never blocked by trees or houses of any sort. It gets full sun from sunrise to sunset. That should do it, right?! :-)
Full sun from sunrise to sunset can't be described as anything other than "full sun" and the weigela should be very happy there!
BTW, keep in mind that if the garden bed is on the north side of your house -- it's on the south side of the house across the street! IOW, whether its on the north or the south side depends on where one is standing :) You were right to consider the amount of possible shade as being of more importance when considering where to plant.
Not to over simplify...but....Planting on the north side of a building or wall, means that the only sun reaching that comes from the north....planting on the south side means that all the light comes from the south....
At any rate your wigelia won't do beans on the north side of the house....depending of course, on how close to the house it is planted.....
But then you already knew that didn't you? LOL!