Skip to main content

Healthy Resilient Seedlings

Leithfield Nursery - A recipe for strong seedlings and healthy soil.

Improving Soil Health Translates into Healthy Seedlings.

With soil health declining, worm counts reducing, a change in approach and the addition of Fish IT has helped Leithfield grow strong, resilient, healthy seedlings.

Leithfield Nursery is a nursery at the bottom of the South Island growing seedlings to sell into the forestry market. Producing up to 15 million seedlings per year, Leithfield has served the market for a long time supplying Pinus Radiata and Douglas Fur. But over time their soil health had degraded and the quality of their seedlings had decreased.

This translated into poorer quality seedlings resulting in reduced revenue, increased costs and reduced successful uptake in the plantations.

The forestry industry has typically used a mix of strong herbicides and pesticides when growing seedlings and this had contributed to the degradation of the soil health at Leithfield. In 2015 the soil was noticeably going backwards.

Lyndon says,

“We were finding that our soil health and our worm counts were deteriorating so much that we were actually seeing dead worms on top of our ground.”

Owner of the nursery, Graham Dodds has always been very proactive in finding ways to improve things on the land and in 2015 Fish IT approached Graham about running some trials on their forestry seedling blocks.

When Fish IT came in and inspected the soil they found a very low worm count and poor soil quality. The decision was made to apply Fish IT to the various blocks as a soil conditioner with a view to improving soil health, lifting worm counts and providing the soil biology with a biostimulant it could use to cycle nutrients for plant uptake.

Soil Health and Nutrient Cycling Improves, Worms are Abundant.

Situated just beside the Edendale Dairy Factory, Leithfield has taken a cyclical approach to managing their blocks of trees and pasture. With each season that passes they are taking the seedling blocks and planting into pasture to help regenerate the soil health. Pine seedlings are nutrient hungry, so by returning the blocks to grass, to graze or produce silage and the like, each seedling block is given the chance to improve its soil condition.

Leithfield uses Fish IT as a soil conditioner applied to the soil on all its blocks as well as a nutrient ‘hit’ (kind of like Red-Bull) as a foliar application.

We are applying 30 L/ha here as a soil conditioner. What we are looking for our soil conditioner to do is to release the nutrients into the seedling as quickly as possible and also into our grass blocks as quickly as possible.”

Lyndon, General Manager and Leithfield Nursery says that their soil health has improved tremendously over the last 5-6 years. Watch the video above for more.

“Progressively through the years our worm count has really gone through the roof and the health of our seedlings has improved dramatically.”

The presence of mycorrhizal fungi around the root structure of the seedling, seen here by the white powdery substance on the roots, is exactly what Lyndon is looking for in his plantations. Fish IT helps to feed the soil biology like these.

Fish IT allows the soil biology to thrive by providing a food source they can then consume to enable them to do their job making the nutrients in the soil plant available. It is a process that is highlighted by the very visible appearance of mycorrhizal fungi on or near the roots of the seedlings.

“Anything that helps to condition the soil has to be beneficial for the mycorrhizal fungi to be able to pick those nutrients up.”

Lifting a seedling from the ground, Lyndon points out the presence of mycorrhizal fungi, a white powdery substance at the base of the plant and around the root zone.

Mycorrhizal fungi are one of the most beneficial organisms in the soil and can be easily identified. If they are present you will see the white ‘powder’ – shown here by Lyndon at the base of the plant. Mycorrhizal fungi colonize plant roots, living partially inside and partially outside the roots. They act as extensions of the roots helping to pick up and cycle nutrients aiding in the functioning of the plant roots.

“We are trying to get as many of those nutrients out of the ground and Fish IT is really helping those nutrients pull through. The more mycorrhizal and the more fine roots that you can get on a seedling the more nutrients are going to be taken up and the healthier the tree is going to be.” 

Lyndon adds that the seedlings are free from browning off and any disease that can be typical of pine seedlings.

Seedlings that are healthy means reduced chemicals and stronger plants.

During the growing season the nursery workers will walk all the seedling blocks at least once a week looking for signs of disease or degradation and also whether the seedlings look hungry and need another boost of nutrients.

Lyndon explains that if the seedlings need a boost, that on an overcast day they will  apply Fish IT directly over seedlings that are over 10cm high. This acts as an additional hit of nutrients to the plant taken up through the leaf.

“What we are really looking for here is to help the plant be healthy and to fight its own diseases. The more nutrients you can get into the plant , the stronger and the healthier the plant is.”

Finally Lyndon adds that the upstream effect of all this is that with the healthier plant, additional fine roots and mycorrhizal fungi they are seeing a higher survival rate out in the planting site once it is planted.

“The ideal situation for our seedlings is to have them out of the ground for no more than 48 hours. The more mycorrhizal fungi and nutrients that have been picked up with the help of Fish IT the survival rates are going to be much higher out in the plantation area.”

And completing the importance of healthy plants to the nursery Lyndon says,

Lyndon talks about the importance of mycorrhizal fungi around the root zone of the seedlings and how Fish IT helps to feed and foster these vital organisms in the soil.

“When you are planting several million seedlings for a corporate client it's a very cost effective thing to have a healthy plant right from the start.”

Learn more about how Fish IT works.

Get in touch