Managing delays in production and planting of native seedlings due to COVID-19 lockdowns — Fact sheet

With the nationwide COVID-19 lockdown in early 2020 and lockdowns since, there was concern that the planting of native trees and shrubs would be delayed.

During the March-April 2020 lockdown, millions of seedlings were in native plant nurseries ready for planting.

Te Uru Rākau – New Zealand Forest Service commissioned Tāne’s Tree Trust to analyse the effects of lockdowns on the production of seedlings in native plant nurseries and on sites to be planted that year.

Methods

For this project Tāne’s Tree Trust reviewed existing information sources and interviewed people in the native plant nursery and planting sectors.

Online surveys were used to get the views of native plant nurseries and people planting natives.

To make reporting on survey results easier, most questions used tick boxes. People selected their answer from a list or chose a rating or percentage value. Surveys were emailed out in late February 2021.

Results

A summary of feedback from each survey is below.

Nursery survey

The COVID-19 lockdown in autumn 2020 happened at the peak time for seed collection. This is an important phase of nursery operations, essential for raising stock for the next year. Growing natives (or exotics) has a strict sequence of activities that must happen through the year to be successful.

Nurseries see themselves as an essential service. They work with living products, similar to animal and food industries. Nursery products need ongoing management during lockdowns and other disruptions.

Native plant nurseries think more flexibility is needed for their operations during future lockdowns. They follow a rigid seasonal pattern, shown below:

  • seed collection in autumn
  • seed preparation to promote good germination
  • sowing seeds in winter to early spring
  • transferring seedlings to pots in late spring
  • hardening off young plants to adjust to being outdoors
  • transporting seedlings safely to planting sites.

Like farms and other rural businesses, nurseries are mostly outdoors. This allows safe work bubbles to be set up for all operations.

Options to manage disruptions to nursery propagation include the following.

  • Topping (trimming the top of a plant to stop vertical growth) to hold stock over for a few months. This is only practical for selected species like shrub hardwood species.
  • Repotting into bigger containers to hold stock until the next planting season. This avoids bound and distorted root systems, but needs more labour and nursery facilities.
  • Collecting and storing more seed to provide flexibility. This risks seeds becoming less able to germinate (grow) over time.

Planter survey

The effect of a disruption at the planting site depends on the time of year, length of the disruption and how severe the restrictions are.

The COVID-19 lockdown in autumn interrupted site preparation just ahead of the main planting season. As a result, planting was later than normal. Planting delays put plants at risk of dying during the dry summer months.

Options for coping with delays in planting and extending the planting season include:

  • planting larger stock, which may be more resilient to delayed planting. This takes up more space for transporting. It is also heavier to handle at planting sites
  • using plant protectors to reduce exposure, and/or mulching to keep the soil moist. Both are expensive and a lot of work
  • selecting hardier species to plant
  • avoiding difficult planting sites.

Practical options for coping with a delay at the planting site include:

  • spraying herbicide on problem woody weeds that can take over during delays at planting sites
  • maintaining grazing of pasture sites - this would need fencing
  • grassing bare sites to stop exotic woody weeds growing – this costs extra.

Conclusion

COVID-19 had a small to moderate effect on nurseries operationally and financially. COVID-19 had less impact on planters. Any long and restricted lockdowns in the future would be a major disruption to native plant nurseries and those preparing and planting sites.

One Billion Trees Programme research

This research was commissioned by the One Billion Trees programme.

Read about other One Billion Trees science projects on the Ministry for Primary Industries’ website.