How to Acclimate Evergreens

Plants grown in a greenhouse must be acclimated carefully before planting or placing them outdoors. This is especially true in hot or sunny locations. Many species should never be grown in full sun. Before purchasing a plant, learn about its sun requirements. Knowing the plants requirements can avoid any damage to the plant by incorrectly giving it the wrong conditions.

NOTE: This is part 2 in a series of 9 articles. For a complete background on how to grow evergreens, we recommend starting from the beginning.

Acclimating Bare-Root Trees

Allow your tree’s roots to soak in water an hour or two before planting. Do not soak the roots for more than 24 hours.

Bare-root trees are not grown in a pot and will not have any soil around their roots – hence the name “bare root”. Our bare-root trees are shipped dormant, which helps them to transplant well and experience less transpiration (water loss) immediately after planting. The best thing you can do for a new tree is to avoid shock as much as possible, so don’t wait until it’s too late in the season to plant. The best time to plant a bare-root tree, or any other bare-root plant, is in the fall or early spring.

Acclimation Steps for Potted & Bagged Trees

If your new trees from Stark Bro’s arrive in pots with tender leafy growth, chances are they were grown in our greenhouses. To acclimate them before planting outdoors, follow these steps:

Keep the plants in their pots and place them in a semi-shaded spot outside for a day, then move them to a sunnier location.
Water the plants upon arrival but let the soil dry to promote the hardening-off process.
Watch for signs of leaf damage and move them to a shaded area with filtered sunlight if needed. Air movement is vital for hardening off the plant, so protect them from harsh winds.
After 2-3 days, if weather conditions allow and soil temperatures remain above 50ºF, plant them outdoors in their permanent location. Plant on a cloudy day for best results.

Please note that these are general recommendations, and factors such as weather and individual plant types may require slight variations to the guidelines. If conditions are too harsh, keep potted plants near a sunny window and treat them like houseplants until the weather improves, then start the hardening-off process.