Blue Whale Trees

Companion species

Try black walnut, flowering dogwood or spicebush.

Pick one native tree or shrub and see what grows with it. The matches come in three groups. Some species share its ground in the wild, and others live under its canopy or are the trees it can be planted beneath. The rest suit the same yard because they want the same sun, soil and climate. Every match is explained on the page, so you can see why a species is listed.

Shrub, 6–12 ft, zones 4–9; full sun, part shade or shade; average or wet soil. Catalog page.

In the yard

Trees to plant it under

Spicebush takes some shade, so it can live beneath these. All are rated hardy in zone 6.

In the yard

Beside it

Plants that want the same sun and soil, for a bed, a hedge or a grove. All are rated hardy in zone 6.

Plan the planting

Be first

Email me when Spicebush or a companion is ready to order

For Spicebush, Florida Maple, Sugarberry, Ohio Buckeye, Bitternut Hickory, River Birch, Red Mulberry, Bottlebrush Buckeye, Virginia Sweetspire, Florida Anise, Strawberry Bush, Wild Black Currant: one email per plant when it is priced or back in stock, and nothing else. Each carries a code for 10% off the plants in that order, not shipping or tax.

How the matches are made

  • Natural communities. Every species we grow is tagged with the communities it lives in: floodplain forests, swamps and wet flats, stream banks, rich moist slopes, dry uplands, sandy barrens, rocky ground, old fields and edges, the forest understory, the Appalachians and the coast.
  • In the wild. Up to eight natives that share one of those communities with it and grow wild in one of its states. The most communities in common come first, then the native range most like its own. A species in a yard list is not repeated here.
  • Under its canopy, or trees to plant it under. Up to six species at least two sizes apart, the smaller one taking part shade or shade: shrubs under a medium tree, shrubs and small trees under a large one.
  • Beside it. Up to six that share a sun with it, the same size first.
  • The order of a yard list. Every yard pick shares a zone, a soil and a state of native range with it. A shared community counts two points, and a shared sun or soil one. Under a canopy, a species of the forest understory counts two more, and one that takes full shade one more. Of equal scores, the one hardy in more of its zones comes first.
  • How far apart. Each yard card links the planting-distance tool with both trees named. The tool gives the gap between them: each one's own spacing from its page, or half of each crown added, unless a page gives a larger distance from other trees. The wild list links the same tool with the chosen tree set, for any next tree you name.
  • Your zone. With a zone chosen, the yard lists keep only species rated hardy in it.
  • Black walnut. The 37 species we grow that the Morton Arboretum lists as sensitive to its juglone are left out of its answer, and it is left out of theirs. Under a walnut, the species on Morton's tolerant lists come first and are marked.
  • Eastern red cedar. The 25 crabapples, hawthorns, serviceberries, chokeberries and mountain ash we grow are left out of its answer, and it is left out of theirs: the cedar-apple, hawthorn, quince and juniper broom rusts live on both, and the University of Minnesota Extension says to keep them a few hundred yards apart.
  • A tree or shrub we do not grow. The 53 common natives under their own group in the menu take the same tests, with their ground, zones, sun, soil and states of native range from their sources (Silvics of North America, the USDA PLANTS Database, the Woody Plant Seed Manual, the Fire Effects Information System and extension and botanical garden pages). The answer says so, links no page, and offers the sign-up for the companions only.

The communities are our own tags. The states of native range are the USDA PLANTS Database's records, read on 2026-09-23 (2026-10-13 for the common natives we do not grow), as the native trees by state tool reads them. Zones, sun and soil are each species' own page, or its record for a common native we do not grow. The juglone lists are the Morton Arboretum's, read on 2026-10-05, which warns that "any list regarding this topic is incomplete and some of the information may be anecdotal." The rusts' hosts are the University of Minnesota Extension's, read on 2026-10-06. What to plant under a big tree and the article on juglone cover the subject.

Sharing a habitat tag does not mean two species always grow side by side, and a tag says nothing about how far apart to plant them. Use the planting-site check for the spot itself, and the growth estimator for how much room each one will want in twenty years.

The address carries the companion species tool's inputs, so a link opens it filled in, and Copy link on a result writes one: species (a plant's slug, the last part of its page's address, such as white-oak), zone (a whole number from 2 to 10, to keep the companions to it), sort (featured, name, price-asc, price-desc, height, hardy or fast). For example, /tools/companions/?species=white-oak&zone=6.