What is a good flowering annual that does well planted under a Magnolia tree?

I have about a four foot sguare garden plated under a Magnilia tree. Every year plants do well until about mid August and then they die off. I don't know if it is because the tree doesn't allow enough sun or what my problem is. I'm a pretty fair gardener and othrer areas in my yard do well. Thanks

What is a good flowering annual that does well planted under a Magnolia tree?
impatiens
Reply:impatiens do well they are shade loving plants also plant caladium they also like shade as well as ferns check plant tags before buying so you can get mostly shade loving plants hostas all around the tree in a circle would look really good and even though they are perennial they will bloom in the summer
Reply:the tree wins in the war for water and nutrients, that's why... pot your plants and tuck them in amongst some mulch in that bed and they'll prob live longer.....of course, you'll need to feed and water them....
Reply:You could try Cyclamen. A corm and flower that does well in the shade and when flowering finishes your left with the nice leaves.
Reply:Pansy or violas - they grow well in sun or shade