Should I leave the salt marsh aster be?



I am trying to grow a native garden however I am conflicted about the salt marsh aster growing in it. Also my garden is located in North East Scarborough. Should I weed them out since they are native to Canada but not Ontario?


Thank you for your question.  Wonderful that you are growing with native species. Native plants have adapted to our climate and soil and the insects and animals that rely on them for food and shelter. Native plants grow naturally in a particular region so your query is well thought out.

The following is some information from a previous question about Salt Marsh Aster:

The eastern annual saltmarsh aster, Symphyotrichum subulatum (formerly Aster subulatus) has naturalized in southwestern Ontario, but is adventive in other locations.  A “naturalized” plant is a non-native plant that does not require human intervention to reproduce/maintain itself in its non-native environment.  An “adventive” plant is one that has become established in an area other than its origin, with the help of humans.  If an adventive plant becomes self-sustaining in its new environment, it is then called naturalized.


The Credit Valley Conservation website ( lists native plants by preferred habitat and provides lists of current Native Plant nurseries in the GTA.

We hope this information will help you make an informed decision about the aster.  All the best in growing your native garden!  Take a look at our Ask a Master Gardener website for ideas – just enter the search term “native” and you’ll find Gardening Guides and responses to prior questions.