I'm sorry to hear that. What a nice idea to remember her. How about one of the deciduous azaleas? I think the ones in the Northern Lights series might work in your zone, but do check first.

They are hardy to zone 4-5. I don't know anything about them though. Will they grow in only part sun? And they won't need any human-given care?

If you want a a small tree that will bloom without much invention you could try some service berries. They bloom quite nicely as well as producing edible berries. Of course witch hazels and their relatives are interesting bloomers that bloom a time of the year when nothing else is blooming and they do like forest settings.

FataMorgana

Yes, the azaleas will grow in part sun. They may not bloom as heavily as with more sun, but they will grow. And yes, other than watering them the first year to get them established (the same as with other plants), they don't need human care.

The suggestions by FataMorgana are also good.

You are going to have to water it to get it established. Fertilizer is overused so that meets your requirements. But what do you have a pruning every year or two?

I don't have an issue with pruning. I just don't want anyone to have to be out caring for it as it's to be planted on property we own but don't live on.

Sounds like you would be better suited with dried flowers.

Lilacs several different types. There are some that will rebloom and or bloom lateer in the summer. Quinces aka Cardinal bushes, bloom in spring then if the season is good have quince apples to the wildlife that your woofer liked to chase. If a small tree is not a problem some of the hawthorns have flowers fruits and color. These are not native so if you want only native plants try some of the native plums. None of the plants bloom all season but will provide a place for you to put a bench and think of your baby.

My old friend Maggie's ashes are under the Witchhazel intermedia Arnold Promise.

{{gwi:1356340}}

Blooms every February, vase shaped, long lived, prune maybe once right after bloom when young, little to no care, woodland edge, well drained slightly acidic. Hardy 5-7, make sure it's a graft to H. virginiana rootstock just to be sure.

maifleur, just a minor correction. There are hawthorn native to the US. There are other varieties that are not. One of my favorite native varieties is the Washington Hawthorn (Crataegus phaenopyrum). I included the USDA link on it below.

Mine love the full sun so I'm not positive how they would behave in a woodland setting.

FataMorgana

Here is a link that might be useful: USDA - Crataegus phaenopyrum

I am glad for the correction. I have seen hawthorns growing as understory plants and also on the north side of a 26 story building with no direct sun. They did get reflections from windows. However for misguided idea of safety they were taken down because some of the berries were hitting the sidewalk. They replaced them with a gravel bed that turned legs.

Thank you all for these suggestions. I think I may plant a few things that bloom at various times of the year. I love that the witch hazel bloom in the snow like that. Also, I like Azaleas. I love lilacs, but I'd have to pay closer attention to just how much sun that spot actually receives because lilacs require quite a bit.