From Agro Vivero del Mediterráneo, we have spent years dedicated body and soul to a crop we are passionate about: the pistachio. Our experience has taught us that the path to a successful and profitable plantation is a marathon, not a sprint. Each stage of tree development is crucial and requires specific knowledge and care. Today we want to share with you, farmers and enthusiasts, a detailed guide on the fascinating growth phase in pistachio cultivation. Join us on this journey from planting a small graft to the majesty of a tree in full production. 🌱

Understanding and correctly managing the growth phase is the cornerstone to ensure not only tree survival, but also their vigor, structure, and ultimately, the profitability of the pistachio plantation. A tree well-formed from its beginnings is a tree that will produce more and for longer, thus optimizing the investment made.

The beginning of the journey: planting and the first year

Every great project begins with a first step. In pistachio cultivation, this step is the choice of plant material and its correct implantation in the ground. At Agro Vivero del Mediterráneo, we place special emphasis on this moment, as the future of the operation will largely depend on it.

Plant choice: a strategic decision

Success begins with the selection of a pistachio plant of the highest quality. We work mainly with UCB-1 rootstocks, recognized for their great vigor, resistance to diseases such as Verticillium, and excellent adaptability to different soil and climate conditions. The desired variety is grafted onto this rootstock, with Kerman being the most widespread due to the quality and caliber of its appreciated nut, and Sirora an increasingly popular alternative due to its precocity and adaptation to our latitudes.

It is fundamental to acquire healthy plants, with a well-developed root system and a clean, well-healed graft point. A lower quality plant can cause problems from day one, delaying its entry into production and being more susceptible to pests and diseases. Therefore, we always advise trusting specialized nurseries that guarantee the genetic and sanitary quality of the plant material.

Land preparation and planting time

Before young plants arrive at their definitive home, the land must be prepared to receive them. We recommend deep subsoiling to decompact the soil and improve drainage and aeration, thus facilitating root development. A prior soil analysis will give us the keys to amendment or basal fertilization needs.

The ideal time for planting in our Mediterranean climate is usually from late autumn to early spring, always avoiding periods of heavy frost. This allows the plant to settle and begin developing its root system before the arrival of summer heat.

The planting frame is another key decision. Traditionally, frames of 7×7 meters or 7×6 meters have been used, which means between 204 and 238 trees per hectare. However, new trends lean towards more intensive frames, such as 6×5 or even 6×4 meters, seeking faster entry into production and greater space optimization. The choice will depend on available machinery, soil fertility, and the management system to be implemented.

The first year: intensive care for good rooting

The first year is undoubtedly the most delicate. The main objective is to ensure plant rooting and promote vigorous initial growth.

• Irrigation: Pistachio is drought-resistant, but during the first year, irrigation is indispensable. Water inputs must be frequent but moderate, maintaining constant moisture in the root ball without waterlogging. A drip irrigation system is the most efficient option, applying short irrigations 2-3 times a week during summer. We are talking about initial allocations of about 1,500 m³/hectare per year.

• Staking: The young plant is fragile and needs a guide. Placing a resistant stake (bamboo, wood, or fiberglass) is essential to guide the growth of the main shoot vertically and protect it from wind action or machinery damage.

• Protection: Using protectors or meshes around the trunk is a highly recommended practice. These protect the tender stem from rodents and rabbits, sunburn, and herbicide damage.

• Weed control: Competition for water and nutrients is fierce during this stage. Keeping the tree pit or planting line free of weeds is crucial. This can be done mechanically, with weed control fabric, or with careful use of herbicides.

• Fertilization: During the first year, fertilization must be very measured. Small doses of nitrogen and phosphorus-rich fertilizers can be applied through fertigation starting in spring, when the plant has already begun to sprout, to stimulate both aerial and root development.

At the end of the first year, if we have done our job well, we will have a plant that has overcome transplant stress, with an expanding root system and a main shoot that has reached, at least, the height at which we will perform training pruning.

The training phase: sculpting the future of the tree (Year 2 to Year 4/5)

Once the first year is overcome, we enter the training phase. During this period, which generally spans from the second to the fourth or fifth year, our main objective is not production, but building a strong, balanced, and well-lit tree structure. Pruning is the fundamental tool at this stage. 🌳

Vase training pruning

The most widespread training system and the one we recommend is the vase. This structure allows excellent light and air penetration throughout the canopy, favoring nut quality and reducing the incidence of fungal diseases.

• Second year: At the beginning of the second spring, we perform the first training cut. The main axis is cut at a height of between 80 and 100 cm from the ground. From the shoots emerging below this cut, we will select between 3 and 4, which will be the future main branches or “arms” of the tree. These shoots must be well distributed around the trunk, as if they were wheel spokes, and with a good insertion angle. The rest of the shoots are removed.

• Third year: In the following winter, the selected main branches are pruned, shortening them to about 40-60 cm in length. We always seek to cut above a bud facing outwards, to favor canopy opening. From the new shoots emerging on each main branch, we will select two to form secondary branches. The goal is to double the number of main branches, going from 3-4 to 6-8 well-distributed secondary branches.

• Fourth and fifth year: We continue with the same philosophy. Thinning pruning is performed to remove branches that cross, grow inwards, or are poorly located. We seek to maintain an open and balanced structure. From this moment on, pruning interventions will be less severe, focusing more on cleaning and maintaining the desired shape.

Mastering training pruning is an art requiring knowledge and foresight. A tree well-formed from a young age will save us many problems in the future and maximize its productive potential. At Agro Vivero del Mediterráneo, we offer technical advisory services to guide farmers in this decisive task.

Nutrition and irrigation during the training phase

During these years, the tree experiences very intense vegetative growth. Water and nutrient needs increase considerably compared to the first year.

• Irrigation: Water allocation increases progressively. We can go from 1,500 m³/ha in the first year to about 2,500-3,500 m³/ha in the fourth or fifth year. It is fundamental to adjust irrigation to tree needs, evaporation, and soil type, avoiding both water stress and waterlogging. Good irrigation management in this phase translates into greater annual growth and, therefore, earlier entry into production.

• Fertilization: Needs focus mainly on nitrogen (N), which is the engine of vegetative growth. Phosphorus (P) remains key for root development and energy transfer, and potassium (K) begins to gain importance as the tree approaches adulthood, as it is directly involved in nut filling and general tree resistance. A balanced fertilization plan could contemplate annual contributions per hectare in the order of 60-80 fertilizer units (FU) of N, 30-40 FU of P₂O₅, and 70-90 FU of K₂O, adjusted according to soil and foliar analyses. Application through fertigation remains the most efficient method.

Entry into production: the first nuts (Year 4 to Year 7)

This is one of the most awaited moments by any farmer. After years of investment, work, and patience, trees begin to yield their first harvests. Entry into production is not a sudden event, but a gradual process. 🥳

Precocity depends on many factors: variety (Sirora is usually earlier than Kerman), rootstock (UCB-1 accelerates entry into production), planting frame, and, above all, management carried out during training years. A well-managed plantation can offer its first commercially interesting harvest in the fifth or sixth year.

First harvests

First productions are usually small and can be somewhat irregular. It is normal to observe:

• Small quantity: A tree in its fifth year could produce between 200 and 500 grams of in-shell pistachio.

• High percentage of blanks: It is common in first harvests to have a high percentage of pistachios that have not filled correctly. This is because the tree is still developing its full potential.

• Incipient alternate bearing: Pistachio is an alternate bearing crop, meaning it alternates years of high production with years of low production. This alternate bearing can manifest from the first harvests.

It is important not to get discouraged. These are normal symptoms of tree youth. As the plantation matures, harvests will stabilize and increase in quantity and quality.

Management during entry into production

During this phase, management becomes more complex, as we must balance vegetative growth with production.

• Production pruning: Pruning changes objective. It is no longer about forming structure, but maintaining it and renewing productive wood. Pistachio produces on previous year’s wood. Pruning will therefore seek to remove old or exhausted wood, thin branches to improve lighting, and stimulate growth of new shoots that will produce in the next campaign.

• Pollination: A crucial aspect! Pistachio is a dioecious species, meaning there are male trees and female trees. Pollination is by wind (anemophilous), so correct distribution of pollinators in plantation is vital. Proportion is usually one male for every 8-10 females. Also, important that male and female flowering coincide in time. For Kerman, most common pollinator is Peter, while for Sirora C-Especial is usually used. Poor pollination is synonymous with harvest full of empty pistachios.

• Fertilization adjustment: Potassium (K) needs skyrocket during production phase. Potassium is essential for sugar transport from leaves to nut, determining caliber and filling. Fertilization plan in this phase could increase potassium doses up to 120-150 FU/ha, maintaining or slightly adjusting nitrogen and phosphorus based on tree vigor and foliar analysis results.

• Pest and disease control: As tree has more leaf mass and production, it becomes more attractive to certain pests and diseases. Necessary to implement monitoring and integrated control program. Some most common threats are aphids (Hyalopterus pruni), pistachio psylla (Agonoscena pistaciae) or fungal diseases like Alternaria or Septoria.

If you are thinking of starting your own project and want to ensure making correct decisions from start, we invite you to contact us. Our team of experts can advise you every step of way.

Full production or maturity phase (From Year 8-10)

Around eighth to tenth year, pistachio plantation enters maturity or full production phase. Trees have reached definitive size and structure completely formed. From this moment, main objective is maintaining high, regular, and high-quality production for as many years as possible. Well-cared pistachio tree can be productive for over 60-70 years.

Productive potential

In this phase, well-managed dryland plantation can reach average productions between 800 and 1,200 kg of in-shell pistachio per hectare. In irrigated conditions, these figures skyrocket, potentially consistently exceeding 2,500 kg/ha , and even reaching peaks over 3,500 kg/ha in “on” or load years. These numbers make pistachio one of most profitable woody crops currently. On our website, we have detailed analysis on profitability of pistachio plantation that can be of great interest.

Management in maturity phase

Management focuses on optimization and maintenance.

• Maintenance and renewal pruning: Annual pruning key to combat alternate bearing. In high load years (“on”), somewhat more intense pruning performed to reduce number of flower buds and prevent tree exhaustion. In low load years (“off”), pruning lighter, seeking to stimulate flower bud formation for next campaign. Goal always maintaining balance between vegetative growth and production.

• Precision irrigation: In irrigation, water most powerful tool to maximize production. During nut filling phase (July-August), tree water needs maximum. Water stress in this period can cause drastic caliber reduction and increase in percentage of blank pistachios. Water allocation in full production can be between 4,000 and 6,000 m³/ha, depending on climate and soil. Use of moisture sensors and monitoring tree water status allow applying precision irrigation, providing just enough water at right time.

• Advanced fertilization: Foliar analyses become indispensable tool. Allow diagnosing tree nutritional status and adjusting fertilization plan precisely. Potassium remains king, but attention must also be paid to micronutrients like zinc (Zn) and boron (B), very important for fruit set and nut quality. Foliar applications of these elements at key moments (pre-flowering, post-harvest) can have very positive impact on production.

• Harvest management: Harvesting takes place between late August and September. Fundamental to determine optimal harvest time to ensure maximum quality. Indicator is when epicarp (skin covering shell) separates easily. Harvesting done mechanically using vibrators with umbrella, allowing large areas to be harvested in short time, crucial for preserving product quality.

Pistachio growth phase long and demanding process, but immensely rewarding. Each year, from planting to maturity, presents own challenges and requires specific care. At Agro Vivero del Mediterráneo, we have accompanied hundreds of farmers on this journey, offering not only best pistachio plants, but also knowledge and technical advice necessary to turn plantation into success story.

Future of pistachio promising. Demand for this appreciated nut continues to grow and prices remain stable and attractive. If considering embarking on this adventure, remember planning and knowledge your best allies. Do not hesitate to invest in quality plant material and seek professional advice.

Ready to take first step? We encourage you to fill out our booking and quote form so we can study your case personally and without obligation. Together, we can make your pistachio cultivation project reach its maximum potential. Future is green, future is pistachio! 💚