Growing the araucaria Growing an araucaria is an exciting endeavor for any gardener looking to add a unique and decorative tree to their outdoor space. Known for its pyramidal shape and distinctive foliage, this tree requires careful attention from variety selection to regular maintenance. Cultivating an araucaria involves understanding its needs for soil, light, and watering to ensure healthy and sustainable growth. This practical guide details all the essential steps for growing an araucaria: variety selection, planting, maintenance, disease and pest prevention, as well as harvesting and preserving seeds to ensure its future.
Table of contents
Choosing the variety of araucaria to grow
Species adapted to the French climate
To cultivate araucaria trees successfully, it is essential to choose a species that can adapt to the local climate. In France, some varieties are more resistant to cold and winter damp than others. Araucaria araucanaThe monkey puzzle tree, also known as the desperados monkey, is the most widespread. It tolerates temperatures as low as -15°C and is well suited to temperate or oceanic climates.
In milder areas, particularly on the Mediterranean or Atlantic coast, one can also consider Araucaria heterophyllaThis species is often grown in pots or indoors, as it does not tolerate frost well. It is more decorative but requires a minimum temperature of around 5°C to remain healthy.
The most common varieties
Apart from these two main species, others can be observed, although they are rarer. Araucaria angustifolia, native to Brazil, appreciates mild and humid climates but cannot tolerate frost. Araucaria bidwilliiOriginating from Australia, it boasts an imposing stature and dense foliage, but its outdoor cultivation remains limited to frost-free areas. For gardeners in northern and eastern France, cultivating theAraucaria araucana It therefore remains the safest choice. It forms a pyramidal tree with an original silhouette, with spirally arranged branches and stiff, deep green leaves.
Selection criteria based on region and exposure
The choice of variety depends on the climate, soil type, and available space. In regions prone to frost, it is best to choose a hardy species and plant it in a location sheltered from north winds. Conversely, in the south or on the coast, a more cold-sensitive species can be grown outdoors if it has well-drained soil and a sunny location.
For growing in pots or greenhouses, Araucaria heterophylla It remains a good compromise, as it adapts easily to indoor cultivation. However, for a spacious garden and deep soil, Araucaria araucana represents the best choice, capable of living for several decades and reaching up to 25m in height.
Where to grow araucaria
Ideal climatic conditions
To successfully cultivate an araucaria, the climatic conditions must be taken into account above all else. This tree thrives in temperate zones with mild winters and moderately warm summers. It tolerates cool conditions but is susceptible to sudden temperature changes and cold winds. Ambient humidity is beneficial, provided the soil is not waterlogged. Araucaria araucana It can grow up to 1,500 m altitude in mountainous regions, provided it is well protected. In contrast, tropical species such as theAraucaria heterophylla prefer a stable climate, without frost or prolonged drought.
Recommended exposure and location
The ideal location for growing an araucaria is a sunny but not scorching spot with plenty of light throughout the day. The tree should be planted in an open area, as its branches spread widely over time. It should not be placed too close to a wall, fence, or other trees to avoid restricting its growth. A space of at least 6 to 8 meters around the trunk is recommended to allow for healthy development. In windy areas, it is best to choose a slightly sheltered spot, such as behind a hedge or mound, to protect the young shoots.
Suitable for planting in the ground or in pots
Growing araucaria in the ground is ideal for regions where winter temperatures remain above -10°C. In colder areas, it is best to grow the araucaria in a pot. This method makes it easier to protect the plant from frost in winter, allowing it to be brought indoors to a sheltered location or a bright conservatory. The pot should be wide and deep, at least 40 to 50 cm in diameter, with a good drainage layer at the bottom (gravel or clay pebbles). The ideal potting mix is a blend of light garden soil, mature compost, and coarse sand. Good drainage is essential to prevent waterlogging, the main cause of root rot.
Preparing the soil for growing araucaria
Soil type and drainage requirements
Before planting an araucaria, it's important to assess the soil type. This tree thrives in deep, light, and well-drained soil. Heavy, clay soils retain too much water, which promotes root rot. In this case, adding coarse sand or gravel can improve the structure. It tolerates slightly acidic soil but dislikes alkaline soils. A pH between 5,5 and 6,5 is ideal. In very compact soils, it's advisable to create a raised planting hole or improve drainage by adding a 10-15 cm layer of gravel to the bottom.
Amendments and pH adjustment
If the soil is poor, an organic amendment before planting is essential. Incorporate some well-rotted compost Well-rotted manure enriches the soil without excess nitrogen, which would promote overly rapid and fragile growth. Adding peat moss can also correct overly alkaline soil. To measure and adjust the pH, it's helpful to perform a test using a gardening kit. In the case of overly calcareous soil, regularly adding acidic organic matter (pine leaves, ericaceous compost, conifer needles) will help balance the growing medium.
Preparing the planting area
Soil preparation should be done at least two weeks before planting the araucaria. Dig a wide and deep hole, approximately 60 to 80 cm (24 to 32 inches), to aerate the soil and facilitate root development. If the soil is heavy, mix the excavated soil with sand and compost before replacing it. It is recommended to install a sturdy stake before planting the young tree, as the araucaria develops a straight trunk that is susceptible to wind damage in its first few years. After planting, water thoroughly to encourage establishment, then keep the soil slightly moist but not waterlogged for the following weeks.
Sowing or planting araucaria
Sowing from seeds: steps and precautions
To grow araucaria from seed, you must first have fresh seeds, as their germination rate decreases rapidly. The cones, harvested when mature, should be carefully opened to extract the intact seeds. Before sowing, soaking the seeds for 24 hours in lukewarm water promotes germination.
Sowing is done in individual pots, in a light mixture of equal parts potting soil, sand, and perlite. The seeds are placed flat, about 2 cm deep, and then lightly covered with substrate. The ideal temperature is between 18 and 22°C, with consistent humidity but without overwatering.
Germination generally takes 3 to 6 weeks. As soon as the first roots appear, the young plants should be handled carefully, as they are fragile. When the seedlings reach 10 to 15 cm, they can be transplanted into a larger container or directly into the ground, depending on the climate.
Planting a young plant purchased from a nursery
For gardeners wanting faster results, it's often best to buy a young, already-formed araucaria. Container-grown specimens root more easily than bare-rooted ones. Planting is best done in spring, once the soil has warmed up and all risk of frost has passed.
The planting hole should be twice as wide as the root ball, with a depth appropriate to the size of the plant. The root collar (the area between the roots and the trunk) should be level with the soil surface. After planting, firmly firm the soil around the trunk and water thoroughly to eliminate air pockets.
Ideal time to plant araucaria
The planting period varies depending on the region and growing method. In open ground, spring (March to May) is the best season, as the mild conditions are conducive to root development. In the south, planting can also be done in autumn, allowing the roots to develop before the start of the growing season.
To grow araucaria in a pot, planting or repotting can be done year-round, except during periods of frost. It is important to monitor the soil moisture during the first few weeks, as prolonged drought or overwatering can hinder establishment. An organic mulch around the base of the plant helps retain moisture and suppress weed growth.
Growing araucaria: how to care for it
Watering and humidity management
To successfully cultivate araucaria trees, watering should be regular but moderate. Young plants require consistently moist but not waterlogged soil, while mature specimens tolerate short periods of drought better. In light, well-drained soil, weekly watering is sufficient during warm weather, supplemented by more frequent watering in dry, windy conditions. It is recommended to check the soil moisture 5-10 cm deep before watering. Mulching around the base of the plant helps retain moisture and reduce evaporation, while also limiting weed competition.
Fertilization and nutrient supply
Araucaria trees thrive in soil slightly enriched with organic matter. Applying compost or a balanced organic fertilizer in the spring promotes growth. Young plants can benefit from additional feeding every 2 to 3 months, while mature trees require less frequent application. It is best to avoid fertilizers high in nitrogen, which stimulate rapid but fragile growth and increase susceptibility to disease. A fertilizer specifically formulated for conifers or a natural amendment (well-rotted manure, compost) is perfectly suitable.
Pruning, staking and growth monitoring
Pruning an araucaria is not essential, except to remove dead or poorly positioned branches. Young plants may need staking for the first two to three years to support the trunk and prevent them from toppling over in strong winds. It is important to regularly check the condition of the foliage and roots to detect signs of stress, disease, or pests. Regular maintenance ensures healthy growth and a robust tree capable of thriving for decades.
Disease monitoring for araucaria cultivation
Major diseases
Growing araucaria trees requires particular attention to certain common diseases. Young plants are susceptible to root rot caused by soil fungi, often linked to excessive moisture or poor drainage. Leaf spots and branch dieback can also occur in cases of water stress or extreme temperatures.
Good Practices documented
To minimize the risk of disease, it is essential to plant the araucaria in well-drained soil and avoid waterlogging around the base of the tree. Choosing a sunny location promotes air circulation around the branches and reduces stagnant moisture. Regularly removing dead or diseased branches prevents the spread of pathogens.
Natural treatments
In case of fungal infection, biological treatments based on copper or sulfur can be applied preventively or curatively. The use of antifungal plant extracts, such as...ortie Horsetail, or other plant-based remedies, strengthens the tree's natural defenses. It is advisable to apply these treatments early in the season, avoiding periods of rain, to maximize their effectiveness.
Cultivating araucaria trees: pest control
Most common insects and parasites
The araucaria tree can be affected by various pests, including scale insects, aphids, and mites. Scale insects attach themselves to branches and leaves, suck the sap, and cause the tree to weaken overall. Aphids mainly infest young shoots, while mites create yellow spots and dry out the foliage.
Chemical-free prevention methods
Prevention is key to limiting the appearance of these pests. Maintaining good air circulation around the tree, removing dead or diseased branches, and regularly inspecting the foliage allows for early detection of infestations. Regular but moderate watering also helps keep the tree vigorous and less susceptible to attack.
Effective and environmentally friendly solutions
When pests are detected, natural methods can be used to control them. Applying neem oil or diluted insecticidal soap effectively controls insects without harming the environment. For light infestations, simply removing scale insects by hand or rinsing the foliage with water may suffice. The goal is to reduce the pest population while preserving the overall health of the araucaria tree.
Growing araucaria: harvesting the seeds
opportune moment
Araucaria seeds are harvested when the cones are mature and begin to open spontaneously, usually in autumn. It is important to choose dry days to avoid humidity, which could encourage mold growth. Young cones do not yet contain viable seeds, and old cones that have fallen to the ground may have lost their ability to germinate.
Seed extraction and drying methods
To extract the seeds, gently open the cones by hand or leave them to dry in a well-ventilated area until the scales separate. Remove the seeds carefully to avoid damaging the embryo. After extraction, light air drying for a few days is sufficient to reduce residual moisture.
Optimal storage conditions
Araucaria seeds are best stored in a cool, dry place away from direct sunlight. Using paper bags or airtight containers with a dry substrate helps prolong their viability. The ideal temperature is between 5 and 10°C, and it is advisable to regularly check the condition of the seeds before sowing to prevent any loss of germination potential.
Conclusion
Growing an araucaria requires patience and regular attention, but the result is well worth the effort. Choosing the right variety for your climate and sun exposure is essential for healthy growth. Careful soil preparation, moderate watering, regular maintenance, and disease and pest prevention allow the tree to develop harmoniously. Harvesting and storing seeds also requires attention to ensure their viability. By following these steps, you can enjoy this unique and decorative tree in your garden or on your patio for many years to come.
FAQ
How to grow araucaria in a pot?
To grow an araucaria in a pot, choose a container with good drainage at least 40 cm in diameter and a light potting mix of garden soil, mature compost, and coarse sand. Place the pot in a bright location, but out of direct sunlight, and water regularly, ensuring no water remains stagnant. In winter, bring the pot indoors or protect it well if the temperature drops below -5°C.
When should I plant araucaria trees in open ground?
Ideally, it should be planted in spring, as soon as all risk of frost has passed, to encourage good root development. In regions with very mild climates, autumn planting is possible provided the soil is well-drained and the location is sheltered. Avoid periods of intense drought or extreme cold, as these increase stress on the tree.
What type of exposure is needed to grow araucaria?
It thrives in full sun or partial shade but needs several hours of regular sunlight for good growth. Avoid areas of deep shade and cold winds, which can slow its development. A south or west-facing location, with protection from prevailing winds and well-drained soil, is ideal.
How to prevent diseases when growing araucaria?
To prevent disease, it is essential to grow araucaria trees in well-drained soil and avoid excessive moisture around the base of the plant, as this promotes root rot. Regularly remove dead or diseased branches to limit the spread of fungi. A preventative treatment with copper or sulfur, applied when the foliage is dry, can strengthen its resistance.
How to fight against pests of the araucaria?
Regularly check your tree for scale insects, aphids, or mites, which weaken it by sucking its sap. For light infestations, rinsing with water or applying diluted insecticidal soap is often enough to control the problem. For more severe infestations, use neem oil or a suitable biological treatment, while avoiding harsh chemicals.
