Pot-in-Pot Nursery Production Guide

1. Pot in Pot Nursery Production Commercial Plant Production

2. A Pot in Pot Nursery

3. What is pot in pot (PIP) production? • A method of producing of shade trees, intermediates, and shrubs using a combination of field growing and container production techniques. • PIP acres in production has been increasing steadily since the 1990’s. • More plants are grown per acre using PIP than field production (Physical and Economic Requirements for Pot-in-pot Nursery Production; McNiel, et al).

4. How does PIP production work? • Two different pots are used: • Socket pot: set into the ground so that 3-6 inches of the container lip is above grade. • Insert pot: this pot contains the growing medium and plant. The insert pot “plugs” into the socket pot.

5. PIP schematic diagram

6. Advantages of PIP • Insulates the roots from temperature fluctuations. • In traditional, above ground, container production it is a well documented fact that high media temperatures kill roots. Media temperatures can exceed 140º F. in the sun.

7. Advantages of PIP • Allows for in-place overwintering. • In traditional container production plants are typically consolidated into quonset houses that are covered with white poly. • Decreases production time from liner to finished product. • Water and fertilizer inputs are controlled by the grower.

8. Advantages of PIP • Reduced water usage. • Most PIP nurseries are drip irrigated. • Eliminates blow over. • Traditional container grown plants with large canopies tend to blow over. • Blow over results in a loss of media and top-dressed fertilizers.

9. Advantages of PIP • Year-round harvesting. • Reduced harvesting labor compared to field production. • Field grown plants are generally harvested when they are dormant. • Digging plants out of the field is labor intensive.

10. Advantages of PIP • Prevents root loss associated with field harvesting. • Reduced shipping costs compared to field grown B&B plants.

11. Disadvantages of PIP • Higher initial cost of installation. • Up front expenses include grading, tiling, purchasing socket and insert pots, irrigation system installation, and liners. • Drainage concerns. • PIP is recommended on sandy soils. It can be accomplished on heavier soils providing they are properly drained. • Without proper drainage, the socket pots may fill up with water.

12. Disadvantages of PIP • Root escape into the socket pot and surrounding soil. • Roots may grow through the drainage holes of both the insert and socket pots.

13. Insert Pot Spin Out treated Socket Pot Solving Root Escape • Apply a copper compound (Spin Out) to the bottom one-third or one-half of the socket pot. • The copper compound will kill the root tips when they reach it.

14. Insert Pot Socket Pot BioBarrier Solving Root Escape • Use BioBarrier. • BioBarrier is a cloth-like material impregnated with Treflan herbicide. • A piece is cut to fit inside the bottom of the socket pot • The Biobarrier releases a gas that will prune the roots of the plant before they can grow out the drainage holes of the insert pot. • Requires a good seal between pots.

15. Spin Out treated fabric liner Insert Pot Socket Pot Solving Root Escape • Use Spin Out-treated fabric bags such as Tex-R Agroliners inside the insert pot.

16. Insert Pot Socket Pot Disadvantages of PIP • Insert and socket pots may stick together making removal difficult. • The bottom of the insert pot may sag, creating an uneven base. • The plants may be exposed to the drying effects of winter’s winds. • Limited flexibility in spacing plants.

17. Growing Media • Pine bark is the main component with particles in the 3/8 – 1/2 inch size. • A common media consists of: • 4 parts pine bark • 1 part peat moss • No sand.

18. Irrigation • Pond or well. • Filtered. • Drip irrigation using: • Micro-sprinklers • Spray stakes • Coverage is important. The entire medium surface must be wetted. This is especially true if you top-dress fertilizers. • Larger pots may require 2 or more nozzles.

19. Irrigation Schematic Spaghetti tube Spray stake or micro-sprinkler Insert pot Socket pot 1 inch black poly lateral irrigation line

20. Micro-sprinklers

21. Spray Stakes

22. The Nursery “Floor” • Bare soil. • Grass buffer strips. • Ground cover fabric.

23. Bare Soil “Floor”

24. Grass Buffer Strips

25. Ground Cover Fabric “Floor”

26. The End