How to Acclimate Blueberry Plants
Acclimate (ac·cli·mate): "To become accustomed to a new climate or to new conditions. Also to harden off a plant."
Acclimating blueberry plants helps to avoid stress to new plants and transplants. It is our strong recommendation for plants that are leafed out and not dormant. Most of our blueberry plants arrive to you potted with tender new growth, since they were grown in the controlled environment of our greenhouses. This tender new growth can be sensitive to things like direct sunlight and sudden changes in temperature, so acclimating blueberry plants to their new environment will help provide them with a great start.
Bare-root plants do not require acclimation and can be planted immediately in the ground or growing container.
NOTE: This is part 2 in a series of 11 articles. For a complete background on how to grow blueberry plants, we recommend starting from the beginning.
Acclimation Steps for Potted Plants
Things that may cause injury to tender new growth in transplants:
- temperatures (below 50ºF or above 90ºF)
- frost snaps
- strong/direct sunlight
- wind
If your new plants or trees from Stark Bro’s arrive in a pot and already display tender leafy growth, then they were likely grown in our greenhouses. Here are a few steps we recommend you follow to acclimate these plants and trees (or harden them off) before planting outdoors:
- Upon arrival, unbox your plants and trees, and keep them in the pots they arrived in. Place them in a sheltered, semi-shady spot outdoors – like on a back porch. After a day or so, move them to a sunnier spot. Water your plants upon arrival, but then allow the top of the soil to dry out – this also contributes to the hardening-off process.
- Observe foliage – if signs of leaf injury appear prior to planting, move those plants or trees back into more filtered sunlight and an area protected from harsh winds. Air movement in outdoor conditions is equally important for hardening off the plant. Cool air helps harden the tender new growth but do bring plants back indoors at night if temperatures are expected to reach close to or below freezing.
- After 2-3 days of acclimating your plants and trees, and if the weather conditions are right, your new plants and trees are ready to be planted outdoors in a permanent location. Your new plants and trees should be able to manage conditions, as long as soil temperatures are expected to stay above 50ºF. For best results, try to plant on a cloudy day.
Please note: these are general recommendations. Your particular growing environment might require a slight variation on these guidelines since some plants can take more time (or less time) than others to harden off. Factors like the current year’s weather, individual plants, and your location may affect the process. If conditions outdoors are too harsh, keep potted plants near a sunny window, water them, and take care of like a houseplant. Then start the process of hardening off your plants.
