Photo by Marguerite Bolt

Anyone who has transplanted hemp—by hand or with equipment—knows planning and attention to detail can make or break a harvest. Making planting mistakes early on can lead to crop mortality and yield reductions, which could ultimately result in financial losses. Here are five tips to help ensure transplanting success in the 2021 field season.

1. Have a planting crew lined up.

Transplanting requires at least several sets of hands. Depending on the operation and style of planting, this could mean having a big crew. Large hemp farms will likely use transplanting equipment; while it is much faster than hand-setting, these farms still need a tractor driver and planting crew. Transplanting could be a multi-day process, especially if farmers plant by hand or have large acreage. Growers should establish their crew before they intend to plant and have a backup plan in case some of their team does not show up. I would recommend growers have a crew figured out at least a month before transplanting, or perhaps earlier if they choose to work with a labor-hiring company.

2. Make sure everything is ready to go before your transplant delivery date.

Growers should prepare fields before they anticipate planting. This work will vary depending on their operations’ production methods. Preparation could mean tilling the field, planting a between-row cover crop, placing trickle tape or laying plastic. Growers will also want to make sure their tractors and other equipment are all working properly. Also consider that starts may need to be “hardened off” if the greenhouse does not offer that service, meaning they will gradually need to become acclimated to the environment. Shade cloths can help with this. Not planning for hardening off could lead to mortality due to sun exposure or wind.

3. Have a plan for planting delays.

Growers may have the best intentions of planting on the date they receive their hemp starts, but sometimes that is not possible. Too much rainfall and frost are common causes of planting postponements in the Midwest. To avoid this problem, plan for a June planting date. If the delay is longer than a day or two, growers need to transfer their hemp starts into larger cells or pots. If growers anticipate a delay before the propagators or greenhouse ships the transplants, that source may even be willing to put plants into larger cells to reduce or prevent root girdling.

4. Do not set plants too deep.

Planting in a way that buries too much of the stem could lead to plant mortality. Setting too deep has been more of a problem than setting too shallow, as placing the stem underground could make plants more susceptible to rotting. However, planting neither too deep nor too shallow (leaving roots exposed) is ideal. Growers should make sure the roots are completely covered with soil and plant no deeper than that.

5. Check on plants after transplanting.

It is important for growers to check the plants right after transplanting to ensure they are standing upright and have good root-to-soil contact. Growers will also want to check frequently for plant mortality, signs of deficiencies (such as wilting due to lack of water or yellowing of leaves) and other stressors. Any plants that are not standing upright may be fixable. If growers observe suffering transplants early after setting, they may be able to replace dead plants with any leftover transplants. Plants do experience some transplant shock, so giving them a day or so helps. If plants are completely wilted after a couple days, they should be replaced.

Marguerite Bolt is the hemp extension specialist at Purdue University’s Department of Agronomy. Bolt is a regular columnist for Hemp Grower.