Answer: These would be happy in a sunny spot, yes, except for the astilbe which will handle morning sun or dappled light all day but not all day or afternoon sun. It also needs a rich, organic, evenly moist yet well drained soil.
I should mention you do have a wide variety of plants. Some such as the willow would prefer a moister soil, others such as the juniper require a well drained site. The heather has very specific soil requirements, needing an acidic soil that is evenly moist yet extremely well drained. The morning glory and snapdragons are annuals and would not be expected to return next year.
You might want to research the plants before planting them so that you can try to meet their needs and keep them healthy so they will thrive in your garden. You should also check their mature sizes to make sure you have space for them to grow into. Here is a web site that you might find useful with your research, you may need to cut and paste the complete url into your browser to make it work correctly:
A few easy to grow perennials that you might consider adding might be daylillies (Hemerocallis), Siberian iris (Iris sibirica), purple coneflower (Echinacea purpurea) and sedums.
Enjoy your plants!
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