Bare root plants are specimens, such as trees, shrubs, and perennials, that are shipped while dormant and completely without soil around the root system. While efficient for transport, this method exposes the roots directly to the elements. The lack of insulating and moisture-retaining soil makes the plant highly susceptible to desiccation, or drying out, which is the greatest threat to survival. This vulnerability significantly accelerates the timeline for successful planting compared to potted plants.
Defining the Immediate Survival Clock
The survival window depends entirely on the condition of the roots upon arrival and the environment they are exposed to. If the roots are completely uncovered and exposed to air, sun, or wind, the plant can suffer irreparable damage from moisture loss in as little as an hour.
A plant kept in its original shipping material (typically damp sphagnum moss, shredded paper, or peat moss) has a slightly extended timeline. This moisture-retaining material can sustain the plant for a few days up to a week, provided the packaging remains sealed and stored in a cool, shaded area. Planting should be prioritized as soon as soil conditions allow to ensure the best chance of establishment.
Critical Temporary Storage Methods
If immediate planting is not possible due to weather or scheduling conflicts, temporary storage methods must be employed to maintain the plant’s dormancy and hydration. Before storage, soak the entire root system in tepid water to rehydrate the tissues. Woody plants (trees and shrubs) should soak for one to two hours, while smaller perennials require only 15 to 20 minutes.
Short-Term Cold Storage
For short-term delays, typically up to two weeks, cold storage is the most effective method for maintaining dormancy. The ideal temperature range is between 33°F and 40°F, which prevents the plant from breaking dormancy. The roots should be kept moist (but not soaking wet) using damp media, sealed in a plastic bag to maintain high humidity (ideally 90 to 95 percent). Avoid storing bare root plants near ripening fruits or vegetables, as they release ethylene gas, which can prematurely end dormancy.
Medium-Term Heeling In
For medium-term delays, extending up to four to six weeks, “heeling in” provides a better solution than refrigeration. This technique involves temporarily burying the roots to prevent them from drying out until the permanent planting site is ready. Dig a shallow trench in a sheltered location and place the plants at an angle, covering the roots completely with loose soil, sand, or compost. Ensure all roots are in firm contact with the moist medium to prevent air pockets and subsequent drying.
Checking for Viability and Damage
Assessing the plant’s health is necessary before planting or storing to ensure it is viable and has not suffered damage during transit. The simplest way to check for life in the stem or trunk is by performing the “scratch test.” Lightly scratch a small area of the bark near the base of the plant using your fingernail or a knife. If the tissue immediately beneath the outer layer is bright green or white, the cambium layer is alive, indicating the plant is viable and dormant. If the exposed layer is brown, black, or dry, that section of the stem is dead.
An assessment of the roots is equally important for determining overall health. Healthy roots should feel firm and pliable, bending slightly rather than snapping when handled. Roots that appear shriveled, brittle, or dry have suffered from desiccation and may not recover. Conversely, roots that are mushy, slimy, or moldy indicate rot, usually caused by being waterlogged or stored with poor air circulation.