THINKING ABOUT GROWING PISTACHIOS? BEN THOMAS Ben Thomas Consulting - PowerPoint PPT Presentation

THINKING ABOUT GROWING PISTACHIOS? BEN THOMAS Ben Thomas Consulting

CLIMATE CONSIDERATIONS • Winter chill – Winter chill needed to break tree dormancy and promote good, even and timely bud break. – Dynamic chill portions. Newsletters provided by PGA – Dormant winter oil applications • Heat requirements – Growth rate of plants depends on heat – Pistachios require sufficient heat to drive kernel development. • Rain during harvest – Increases risk of disease (e.g. anthracnose in 2011) – Delays harvest which can lead to more shell staining and downgrading of product • Frost – Pistachios, like other tree crops, are sensitive to frost close to or shortly after bud burst Slide 2

DYNAMIC CHILL PORTIONS - MILDURA Slide 3

CLIMATE CONSIDERATIONS • Winter chill – Winter chill needed to break tree dormancy and promote good, even and timely bud break. – Dynamic chill portions. Newsletters provided by PGA – Dormant winter oil applications • Heat requirements – Growth rate of plants depends on heat – Pistachios require sufficient heat to drive kernel development. • Rain during harvest – Increases risk of disease (e.g. anthracnose in 2011) – Delays harvest which can lead to more shell staining and downgrading of product • Frost – Pistachios, like other tree crops, are sensitive to frost close to or shortly after bud burst Slide 4

POTENTIAL FROST DAYS Slide 5

SOIL • Soil requirements – Pistachios often planted on less favourable soils – Like other tree crops, perform better with favourable soil conditions (i.e. neutral ph, >60cm potential root depth above restricting soil layers) • Soil information – Good general information available online. – Use soil surveyor to provide detailed soils information which can be used to design irrigation systems etc. – Poor drainage and waterlogging are key considerations • Amelioration and preplant fertilisers – Preplant soil analyses will indicate whether soil ameliorants (lime, gypsum, organic matter) and/or preplant fertilisers are needed. Slide 6

WATER • Source of water – River or bore – Pipeline and pumping costs – Water quality • Irrigation requirements – Theoretical water requirements based on evaporation and rainfall commonly 12 - 13ML/ha – Pistachios have a reputation of being drought tolerant but require considerable irrigation for optimal performance. Slide 7

ROOTSTOCKS AND VARIETIES • Rootstocks – Most recent Australian plantings have used Pioneer Gold I (PG I) or UC Berkeley I (UCB I) rootstocks. – PG I is Pistacia integerrima whilst UCB I is a hybrid rootstock ( P. atlantica x. P. integerrima ) – Pistacia terebinthus and P. atlantica are older rootstocks and were commonly planted in the early days of the Australian industry – The rootstocks vary in vigour, cold tolerance, susceptibility to diseases, salinity tolerance, micronutrient uptake efficiency. – Experience in Australia with UCB I is limited but it appears to be more vigorous than PG I. • Varieties – Sirora was bred for Australian conditions and is the main variety grown. – Kerman is the main variety grown in California. Slide 8

OTHER CONSIDERATIONS • Juvenility – Pistachio trees have a long juvenile period (6-8 years) before they start producing fruit • Male tree percentages – Pistachio is dioecious (meaning ‘two houses’) and so male flowers are borne on one tree and female flowers on another – Pistachio is wind pollinated and so male trees are interspersed through the orchard – Initial plantings in Australia had high male percentages (8-12%) but given the amount of pollen produced, more recent plantings use 4% male trees • Planting density – Many growers are now looking at denser plantings to improve early production especially given the long juvenile period. Slide 9

OTHER CONSIDERATIONS • Pest and disease – Pistachio in Australia have few pests. Key diseases are anthracnose , Xanthomonas and Botryosphaeria shoot and panicle blight. • Biennial cropping – Pistachios will biennial crop meaning alternate ‘on-crop’ and ‘off-crop’ seasons. • Hulling and processing – Pistachios need to be hulled as soon as possible following harvest to maximise quality. There is one major processor in Australia based at Robinvale. Slide 10

FIRST YEAR • Good establishment – Tree losses kept to a minimum. – Keep a close watch on irrigation. • Solid but not excessive growth – Key aim is having a rootstock that can be budded in January. – Ideal rootstock for budding is about pencil to little finger thickness. – Allow scion to grow for the rest of the season. • Key management issues – Water, wind and weeds! – Windbreaks – permanent or temporary? – Cover cropping – Staking options – Tree guards – Nutrition Slide 11

FIRST YEAR – PLANTING AND ESTABLISHMENT Slide 12

COVER CROPPING Slide 13

WINDBREAKS Slide 14

FIRST YEAR – GROWTH OF NEW BUD Slide 15

FIRST YEAR – TRADITIONAL Slide 16

FIRST YEAR – MODIFIED CENTRAL LEADER Slide 17

SECOND AND THIRD YEAR • Vigour and training – SECOND YEAR – Traditional training – aiming to establish tree framework. Requires multiple training passes to develop primary, secondary and tertiary branches. – Modified central leader training – Trees at desired height can be headed in winter prior to second growing season. Minimal in-season training. • Vigour and training – THIRD YEAR – Traditional training – continue to develop tree framework. – Modified central leader training – Primary scaffold limbs selected in winter prior to third growing season. Minimal in-season training. • Key management issues – Water, wind and weeds! – Tree guards – Rootstock – Nutrition Slide 18

SECOND YEAR – MODIFIED CENTRAL LEADER Slide 19

SECOND YEAR – TRADITIONAL Slide 20

NUTRITION - YOUNG TREES • Macronutrients – Nitrogen • Small and regular feeds. • Minimise potential losses of nitrogen via leaching etc. • Which forms of fertiliser? – Phosphorus • Preplant applications • Can consider small applications through fertigation in spring – Potassium • Preplant applications – often not necessary • Can consider small applications through fertigation in spring • More important once trees start cropping Slide 21

NUTRITION – YOUNG TREES • Micronutrients – Zinc • Young trees particularly susceptible. • Zinc immobile in plants so regular zinc foliar nutrient sprays needed to ensure new growth is treated. – Copper • Have observed symptoms on young trees in recent seasons. • Regular copper chelate foliar nutrient sprays appear to be effective. – Manganese • If mancozeb based disease management sprays applied, the young trees should receive sufficient manganese. – Iron • Common in spring especially if soils are wet. • EDDHA-chelated iron applied through fertigation is best treatment option. Iron foliar nutrient sprays not as effective. Slide 22

COPPER DEFICIENCY Slide 23

IRON DEFICIENCY Slide 24