Norfolk Island pine has soft evergreen needles and a symmetrical form that give it a stately look as a holiday decoration or long-lived houseplant. They bring joy well beyond the holidays but are a bit of a Goldilocks when it comes to watering. Learn how to balance your Norfolk pine’s water needs for fresh, green growth with garden expert Katherine Rowe.
Norfolk Island pines are graceful, needled evergreen trees that brighten the winter season, but may require more water than other coniferous plants in your collection. We see them near holiday time, where they make wonderful gifts for the houseplant lover in addition to seasonal tabletop displays. They grow well year-round indoors, and in warm, mild climates (zones 9 to 11), they move to the landscape to become tall specimen trees.
The evergreens are low-maintenance in the right situation with ample light and water. Regular irrgation is part of the balance of care—they like soils that aren’t too wet or dry. In the ground, they need little irrigation once established. In a container, they require it more frequently since pots dry out more quickly, indoors or out.
Knowing what to look for helps determine a regimen for that just right amount of water for your Norfolk Island pine tree to flourish.
Norfolk Island pine (Araucaria heterophylla) lends a lush, tropical look to the garden or home with its pyramidal shape, symmetrical, whorled branches, and soft, deep green needles. The trees are not true pines but a member of an ancient family (Araucariaceae) of pre-historic conifers.
Captain James Cook discovered the evergreens on his second voyage (1772-1775) on an uninhabited island off the coast of Australia. In their native range, they grow along seaside cliffs and in temperate rainforests. The “pines” grow up to 200 feet tall, with trunks six feet in diameter.
Norfolk Island pine trees made their way into cultivation in 1793 and now grow worldwide, especially in coastal, sub-tropical climates with lots of water from rainfall and humidity. And, of course, they are kept as beloved houseplants. They do best in the morning sun and bright light in well-draining, acidic soils.
The top cause of decline in potted Norfolks is overwatering. We sometimes nurture them too much. In their Oceania habitat, they experience regular moisture through humidity and soaking rains, followed by periods of drying out. Volcanic soils are fertile, porous, and well-draining. The tropicals prefer moist, but not oversaturated, soils.
Prolonged saturation leads to root problems. Soggy potting media causes decaying roots, where they can’t uptake moisture and nutrients to support the upper growth. Fungal root rot from overwatering is a primary cause of loss.
Underwatering is another stressor, forcing the plant to conserve energy to survive. Moisture fluctuations lead to weak roots and less robust upper growth. Branches will brown and drop if water fluctuates widely and stresses the plant.
A good rule of thumb for potted Norfolk Island pine trees is to water when the top one inch of soil feels dry to the touch (about knuckle deep). Frequency is usually once a week or two, depending on the growing environment. In more humid environments, they may not need as much irrigation.
Err on the dry side rather than overwatering, but don’t allow soil to dry out completely. Norfolk Island pine needs soil with just enough moisture – not too wet or dry. It can tolerate somewhat drier soils but not constantly damp or overly dry.
A few factors influence how often to irrigate, including the type of container. Terra cotta pots are porous and tend to dry out more quickly. The porosity and airflow benefits roots but may need irrigation more often. Plastic retains moisture longer, which can be helpful in reducing sessions, but calls for a watchful eye to prevent oversaturation.
Plant size and potting medium are additional factors. Well-draining soils are essential; high-quality mixes formulated for pots retain moisture in addition to having good aeration and drainage. Large plants will soak up the moisture, though they are more drought-tolerant with larger root systems. Young plants in smaller pots require it regularly as they quickly develop new roots and leafy growth.
Lighting, seasonality, and growing environment also play into how quickly soils dry. Trees in direct sun require more soil moisture, while those in bright, indirect light absorb and evaporate more slowly. In summer, active growth and warm temperatures draw more water, while winter reduces demand. Also, the specific microclimate creates variables in how quickly the soil dries (arid situations versus humid ones, for example).
When the surface is soil to that inch or so depth, irrigate thoroughly at the tree’s base until water flows through the pot’s drainage holes. Regular, as-needed deep watering is more beneficial than shallow, more frequent sessions.
Some gardeners find it easier to irrigate from under the pot, filling a deep saucer with water for the soil and roots to draw into the pot.
Whether top or bottom watering, remove the catchment tray after being allowed to drain. Emptying the dish ensures the pot doesn’t sit in water and take in excess moisture.
Since moisture imbalances happen, it helps to know what to look for to correct the course. The soil will feel wet, sticky, and spongey (too much water) or dry, crumbly, and dusty (not enough). ]
Green needles will drop from overwatering. Leaves may turn yellow and brown and may drop in both cases, but branches will wilt as a sign of underwatering. If caught early enough, conditions may recover to regenerate healthy roots.
There are a few methods to increase air moisture. The first is to group houseplants together. Create a little jungle where evaporation, transpiration, and surrounding soil moisture raise surrounding conditions.
Another is to place the Norfolk Island pine tree’s container near a tray of pebbles filled with water. The pots should sit close to the tray to avoid excess saturation. Humidifiers, too, work quickly. Air circulation is equally important to prevent excess moisture on leaves and stems from promoting disease. With a lack of natural breezes, a fan or humidifier works to increase airflow.