Management of Mature Coffee
Acknowledgment: This guide is adapted from the Coffee Industry Corporation (CIC) PNG Coffee Handbook 2016. We have simplified the content for easier understanding by farmers.
1. Introduction
o Mature coffee trees need good management to stay healthy and productive.
o There are two main management systems:
§ High Input System – unshaded coffee with fertiliser and good care; produces higher yields.
§ Low Input System – shaded smallholder coffee with lower fertiliser use; moderate yields.
o This section covers nutrition and pruning, which are key for maintaining strong and high-yielding trees.
2. Definition of Mature Coffee
o Mature coffee means trees that have started to bear cherries.
o Tall varieties: mature after 2 years.
o Compact (short) varieties: mature after 1 year.
3. Potential Yields
o Coffee begins producing in the 2nd year after planting.
o Tall coffee: small crop in year 2, highest in years 4–5.
o Compact coffee: good crop from year 2, maximum in years 4–5.
o After this, yields slowly decline unless trees are pruned and renewed.
o Regular pruning and good care help maintain production for many years.
4. Nutrition of Mature Coffee
o Fertiliser helps keep trees strong, improve yields, and prevent yellowing leaves.
o Shaded coffee needs less fertiliser; unshaded coffee needs more.
o Fertiliser needs depend on:
§ Soil fertility and drainage
§ Shade level
§ Coffee age
§ Expected yield and management level
o Too little fertiliser weakens trees; too much wastes money and causes soft growth.
o Always plan fertiliser use before the growing season.
5. Main Nutrients and Fertiliser Types
o Coffee mainly needs:
§ Nitrogen (N) – strong leaves and growth.
§ Phosphorus (P) – roots and early growth.
§ Potassium (K) – fruit growth and disease resistance.
o Recommended ratio in PNG: N:P:K = 8.5:1:8.5.
o Common fertilisers:
§ Compound: 13:3:20 + MgO (best general fertiliser).
§ Nitrogen: Urea, Ammonium Sulphate.
§ Phosphorus: TSP (Triple Superphosphate) or DAP.
§ Potassium: Muriate of Potash (KCl).
§ Magnesium: Kieserite or dolomite.
o Foliar fertilisers – sprayed on leaves to boost growth or correct yellowing.
o Organic fertilisers – compost, coffee pulp, manure, or leaf litter help improve soil health.
6. Fertiliser Timing and Application
o Apply fertiliser at the right times for best results:
§ Nitrogen: 4 times (Sept/Oct, Nov/Dec, Jan/Feb, Mar/Apr).
§ Potassium: 2 times (Nov/Dec, Jan/Feb).
§ Foliar sprays: 3 times (Jan, Mar, and dry season Jul–Sept).
o Apply fertiliser around the drip line (under the edge of the leaves).
o Keep fertiliser 10–15 cm away from the stem.
o Lightly mix into soil or water after application.
o Wash hands and tools after handling fertiliser.
7. Fertiliser Programs
o High Input (Unshaded Coffee):
§ Use compound fertiliser plus extra N and K as needed.
§ Apply 4 times per year.
o Low Input (Shaded Coffee):
§ Apply 13:3:20 + MgO twice per year (Oct/Nov and Jan/Feb).
§ Use compost and coffee skins to save on fertiliser cost.
o Very Low Input (Heavily Shaded Coffee):
§ Fertiliser may not be necessary if leaf litter, shade trees, and coffee pulp are returned to the soil.
8. Pruning
o Pruning keeps trees healthy, improves yield, and makes harvesting easier.
o It helps manage tree shape, improve air movement, reduce disease, and encourage new productive growth.
o Pruning tools needed:
§ Secateurs (hand clippers)
§ Pruning saw
§ Measuring stick
§ Power saw (for old thick stems)
9. Types of Pruning Operations
o Training (Formative Pruning):
§ Capping young seedlings during the first two years to encourage strong branch growth.
o Skirting:
§ Removing lower branches up to 60 cm above the ground.
o Handling:
§ Removing unwanted vegetative growth that competes for nutrients.
o Desuckering:
§ Removing upright shoots (suckers) near the main stem.
o Centring:
§ Keeping the tree open in the middle for air and light.
o Main (Maintenance) Pruning:
§ Removing dead, weak, or interlocking branches after harvest.
o Stumping:
§ Cutting all bearing stems to renew growth after 4–7 years.
o Recycle Pruning:
§ Removing some old stems and keeping others to maintain regular cropping.
o Sucker Selection:
§ Keeping only strong, well-spaced suckers to replace old stems.
10. Objectives of Pruning
· Focus the tree’s energy on productive branches.
· Produce regular crops (avoid overbearing and poor crops the next year).
· Keep trees short for easy picking and spraying.
· Reduce disease by improving airflow and light.
· Renew old trees and increase productivity.
11. Pruning Systems
· Single Stem System: one main upright stem per tree (good for compact varieties).
· Multiple Stem System: two or more stems per tree (best for tall varieties and smallholders).
· Change production cycles every 4–7 years depending on altitude and variety.
· Multiple stem systems are easier for farmers and reduce risk of total crop loss.
12. Factors Affecting Pruning System Choice
· Growth Rate: slow-growing coffee at high altitude suits single stem systems.
· Spacing:
o Wide spacing – more stems allowed.
o Close spacing – single stem system is easier.
· Variety:
o Dwarf types (Catimor, Caturra) – single stem.
o Tall types – multiple stem.
· Management: depends on field size, tools, terrain, and labour available.
13. Main Pruning Practices
· Start pruning tall varieties in the third year, compact types in the second year.
· Main Pruning (Aug–Oct, after harvest):
o Remove lower primary branches to control tree height.
o Remove all suckers and secondary shoots near the stem.
o Cut away inward, downward, or crossing branches.
o Keep 2–4 healthy branches on each main branch for fruiting.
· Disease Precaution: disinfect pruning tools after working on diseased trees to avoid spreading infections.
14. Handling and Desuckering
· Remove unwanted vegetative growth and suckers every 2–4 months.
· This prevents competition for nutrients and water.
· Regular handling and desuckering open up the canopy for better light, flowering, and air flow.
15. Changing the Production Cycle
· Multiple Stem Coffee:
o Remove old lower branches after two years of cropping.
o Leave one or two strong stems and cut others at 30–45 cm above ground.
o Cut at a 45° angle away from the stem to prevent rot.
o Select strong, well-placed suckers to replace removed stems.
o Cycle change takes about 12–24 months depending on shade and altitude.
· Single Stem Coffee:
o Remove branches on one side (sunny side) to encourage new sucker growth.
o Cut a small notch at 45 cm height to trigger sucker sprouting.
o Remove the old head after new suckers are strong.
· Stumping:
o Cut all stems at 30–45 cm high to start fresh growth.
o Leave one “lung branch” (lowest branch) to keep the stump alive.
o Replace about 20% of trees each year to maintain production.
16. Sucker Selection
· Begin when suckers are 10–15 cm tall.
· Keep only 2–3 strong, well-spaced suckers per stump.
· Remove weak, crowded, or very low suckers (<15 cm from ground).
· Continue selection regularly to ensure even growth.
17. Alternative Pruning (No Cycle Change)
· Some farmers remove and replace one upright each year.
· Keeps trees at different ages with continuous yields.
· Advantage: no yield loss during renewal.
· Disadvantage: careful management needed to prevent shading of new shoots.
Key Tips for Farmers
· Always prune after the main harvest and before new flowering.
· Keep trees short and open — sunlight and air are your friends.
· Regularly remove unwanted shoots and weak branches.
· Disinfect tools after pruning diseased trees.
· Recycle pruned branches and leaves into compost to improve soil.