Plants don’t have the option to get up and move to a new location if they don’t like where they’re planted. However, we often transplant them if we don’t like where they are planted. We also start seeds in small pots with the intention of moving the plants, as is the case of nursery grown plants. Since relocating is against a plant’s nature, we have to assume it isn’t particularly good for them. At the cellular level, this is how a plant responds to transplanting.
At the very tip of the root fiber, all plants grow a root cap. These specialized cells are a little more rigid for pushing through the soil. Just past the root cap, the cells are called the apical meristem. The cells here are like human stem cells; they could morph into any type of specialized cell. Apical cells are found throughout the plant, but they are concentrated in the meristem locations – at the ends of the roots and tips of the branches.
When transplanting, many of the root caps and apical meristems are either damaged or intentionally removed. This slows the growth of the plant as it must grow new ones from the root nodes (which are like branch buds but on the roots). Just like I explained regarding pruning in this blog post, the balance of the hormone auxin is disrupted which encourages the root zone to be thicker. In the long run, this is good for the plant. At the time of transplant, however, it can cause transplant shock.
One way to help the plant through transplanting is to water with a root stimulator product. These products are fertilizers with a synthetic root hormone. The root hormone jump starts the healing process of growing new root tips. You can also remove some of the branches, foliage, and flowers. Reducing the size of the plant is especially important when relocating plants in the landscape. The reduced amount of root fibers just can’t support the same amount of top foliage.
Another cause of transplant shock is moving the plant to a drastically different environment; such as, from the warm, still seed tray to a cold, windy garden plot. To help the plant through this shock, you can “harden off” the seedlings by introducing them to their new environment a little at a time. (To be honest, I’m rather lazy about hardening off. My seedlings typically get only 1 or 2 days of moving outside during the day and inside at night before I put them in the garden.)
If you are planting annual container gardens, you may find this previous blog post helpful: How to Plant Container Gardens
These resources from CSU Extension are also excellent:
