We have consistently observed that plants are able to tolerate freezing temperatures without damage when they are supported with balanced nutrition. It is particularly important that they not have excessive nitrogen.
These seedlings were grown in two different types of soilless media. The seedlings on the left are grown in media from Keystone BioAg, which has compost, biology, and soil amendments added to balance nutrition. The seedlings on the right are in standard peat moss based growing media.
Temperatures dropped to 27 degrees F (-3 C) one morning and the plants with balanced nutrition show no impact, while the plants on the conventional media are obviously burned.
What if we balanced row starter fertilizer nutrients with the intention of developing freeze resistance, how might the blend be different. Liquid N and P would certainly be excluded from the mix, and microbial populations and plant health would improve.
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