There is an old grower's adage about plant size -- "If it's not growing, it's dead". Aware of this truism, Johnson's Nursery provides a range of mature heights and spreads for shrubs, trees, and evergreens. A plant’s mature size and how well it performs commonly depends on a range of factors like the site where it’s planted. We’ve scouted box stores and have seen potted Emerald Arborvitaes with a tag saying it gets 6 feet tall – which is true – it will. We often stock beautiful 5 & 6 foot B&B Emerald Arborvitaes in our holding yards, and we guarantee you they will keep growing...up to 25-30 feet tall.
Commonly (but not always) the taller-listed mature size plants grow faster. Emerald Arborvitae grow fairly fast, so we are able to stock a range of sizes. We often get requests for evergreens or trees that won't grow taller than 6 feet, but the client wants to start with a 6 foot tall plant. Without lots of maintenance, that isn't going to happen on most trees. And, again, “if it’s not growing, it’s dead.”
Featured image: Pyramidal Arborvitae, Thuja occ. 'Pyramidalis', planted in the 1980's
Plants often listed as "topping out at 6+ feet", like Green Mountain Boxwood, are rarely salable in that size because they are very slow growing. The larger you go in the beginning, the larger investment is needed because these plants were nurtured and maintained with special care while growing. Or if the plant is container grown, it may have been upgraded to a larger container in production.
You can find gorgeous, field-grown Specimen Trees at Johnson's Nursery, but they come with a larger price tag than the smaller, southern-grown #2 containers found at box stores. Be aware! Sometimes those great deals aren't so great. If the plants were grown and shipped from the Deep South, they will likely struggle to survive Wisconsin winters - we see it often - but that's another topic for another day.
Please do your homework prior to any plant purchases. It will save you loads of head and heartache in the future.