Irrigation is go – A dry season at last
Jonathan Brookes AgFirst HB Ltd
As I write this article, we are seeing the driest soil conditions in the last four years. It looks to be shaping up to be a season where irrigation use will once again be a necessary consideration for Hawke’s Bay fruit growers.
Years of looking at soil moisture monitoring results have taught me that in many parts of the Heretaunga plains, the basic input / output calculation of soil moisture less Evapotranspiration (Et) plus rainfall does not guarantee an accurate soil moisture status. The influence of rain in the river headwaters and how that travels into groundwater can often “freshen up” a soil even with dry local conditions. Open drains can be good indicators of what is happening at a deep level, the deeper readings of soil moisture monitoring sites are also useful for this.
The seasonal soil moisture needs of specific blocks of fruit also needs to be well understood. A significant deficit of soil moisture can affect fruit size, reduce shoot growth and increase the risk of sunburn and biennial bearing in many fruit crops. However, soil rootzone drying in the right block at the right time, can be used to control excessive vigour and improve fruit dry matter and brix levels.
Irrigation systems need to be checked to ensure they are working efficiently and effectively, with irrigation run times set to ensure correct amount of water is getting to (and stopping in) the soil zones where you require it. Check for good filtration, manage leaks, and overall application uniformity.
Keep an eye on your total use as this is necessary to keep within consent parameters but can also indicate other problems such as leaks.
Due to our relatively kind climate the need for irrigation excellence has historically not been easily justified, but it is important to consider that the best seasons for fruit in Hawke’s Bay are generally dry years with crops that have well managed irrigation applied to them.
The need to make improvements to orchard irrigation management will only continue to become more important into the future. Compliance and social license needs, fruit quality, maximizing profitability and reduction in overall management costs all point to a need to get better at managing irrigation.
It was the driest spring the region has had for some time and rivalled the 2012-13 spring, which heralded one of the region’s worst droughts. It was the driest spring recorded at the Council’s Bridge Pa site on the Heretaunga Plains and contributed to a run of five consecutive months of below normal rainfall there. The lack of rain meant river flows, groundwater and soil moisture have all been running below average levels for the time of year. Warmer than average temperatures and, at times, windy conditions have only accelerated the drying trend.
As we run into Christmas, we’ve had some meaty showers traverse parts of the region and as I write, northern Hawke’s Bay has been doused with rain for a few days, with other areas seeing some of it. Unsettled weather continues as we make our way to the New Year. It seems we are being gifted some relief for Christmas.
Previous seasonal forecasts suggested our weather could start to turn. The pattern of higher than normal pressure extending over eastern and southern New Zealand was expected to progressively weaken and shift south, while lower than normal pressure extended eastward over the northern Tasman Sea. The current forecasts continue that theme. It gives us an easterly flow that arrives across seas that are considerably warmer than normal and enable plenty of moisture to be picked up enroute. We may not have an official La Niña but there are still hints of a La Niña influence. Summer rainfall could be near or above normal by the time the season ends and be accompanied by a good level of warmth.
All the best,
Kathleen
NZAPI has begun a five-year project to find new and more effective ways to control bronze beetle after successfully securing additional funding from MPI.
The project is backed by $888,630 of funding from the Ministry for Primary Industries Sustainable Food and Fibre Futures Fund, with NZAPI investing $598,370.
The project will develop and trial new biocontrol products and develop a trap to monitor the beetle’s presence in orchards. It will also test biopesticides that are available in New Zealand and internationally that could be applied to the soil or tree, as well the use of endophyte grasses that might affect bronze beetle larvae. Bronze beetle chews through growing fruitlets leaving apples unsuitable for harvesting and eating. It can damage up to 25 percent of an organic apple crop and costs growers more than $13,000/ha per year.
NZAPI Research and Development Programme Manager Rachel Kilmister says the project seeks to develop a trap to help monitor populations of the pest and determine new bio control options. “Organic growers cultivate the soil to control the bugs, that disrupts the larvae and prevents the beetle appearing during spring. “Organic growers will often do about 11 or 12 cultivation passes during October and November, which does provide a level of control, but unfortunately not enough. It’s also less sustainable long-term as cultivation isn’t ideal for tree or soil health.
“In this research we’ll test pesticides that are available in New Zealand, and internationally, which can be applied to the soil or the tree. We’ll also look at whether endophyte grasses in and around an apple orchard emit natural chemicals into the soil that affect the bronze beetle larvae.” This latest research programme is a part of NZAPI’s research and development programme, which is currently running projects for fruit fly cold treatment, mealybug and more.
Late season Vigour management – Have you got the tiger by the tail?
By Meg Becker
Balancing shoot growth (vigour) is critical to good fruit production. Leaves supply all the energy for tree growth and fruit development, but shoots are greedy and excessive vigour will limit fruit size, yield, and quality.
Deficit irrigation. The first sign of water stress (before impacting fruit size) is the termination of vegetative shoots. This is a common practice, however, should be carefully managed so as not to impact fruit quality outcomes.
Summer pruning has multiple benefits, letting light into the canopy which improves fruit colour and sets buds up for next season. Removing shoots that generate carbohydrate that is not being partitioned into cropload reduces tree vigour.
Cropload is the most effective form of vigour management in any canopy system, however, achieving appropriate croploads in a high vigour block can prove challenging. Altering the leaf to fruit ratio helps improve vigour responses.
Plant growth regulators (PGRs) are an effective tool for managing vigour. Ethephon (Ethrel) and Prohexadione-Calcium (Regalis) are the two most broadly used in pipfruit.
Regalis suppresses growth-promoting plant hormone synthesis resulting in shorter internodes (shorter shoots) and less vigour within the plant in that growing season.
Ethrel is often used as an alternative and supports return bloom (important in a high vigour canopy).
These two products may be used in unison in excessively vigorous blocks.
Post-harvest pruning cuts can made while the tree is still in leaf. In doing this, the carbohydrate reserves are removed from the tree prior to senescence – managing the vigour response at the start of the next growing season. If you miss this window or need to spread labour, pruning at full bloom can be just as effective, this can also be beneficial in blocks where you need to ensure flower numbers prior to branch removal.
Summer girdling can decrease vigour and improve fruit size and return bloom when done correctly. Girdling can be carried out from petal fall through to the end of November/early December. The efficiency of girdling diminishes later in the season.
The depth of the girdle determines success in vigour management. The bark, phloem and cambium tissue should be removed down to the hard white xylem tissue.
Two opposing half C cuts, overlapping and, approximately 50mm apart – the closer the cuts, the harsher the girdle.
As a last resort, root pruning may be used when a block is completely out of control and everything else has failed. Root pruning is harsh, and after the last there wet seasons would be a last resort. Root pruning is also known to reduce fruit size outcomes.
Kia ora koutou,
The EIT year is ending and we are not much wiser as to what the future holds for our institution. What we have been told is that every individual program is being audited against a viability matrix, and any ‘under-performers’ will be closely scrutinized, and quickly removed from our offerings.
What this means is that EIT needs your support – we need enrolments for both our Fruit Production and Post Harvest Diploma programs and a solid steady stream into Certificate of Primary Industry Operation Skills and Level 3 and 4 fruit production courses. If we lose any of these programs, we will lose staff, and then the capacity to deliver in the future, so please continue to support us as you always have, but also, if you can organize enrolments before the end of the year, that will provide evidence to external auditors that we are working in partnership with our local industry, and are an important cog in developing capability for the primary production exports.
Steven and I are on the road and the phone encouraging students to get work in, aware of how busy they are getting at work. Our teaching is just about finished, so please reach out if your student is struggling with anything.
Noho ora mai
Clare, Steven, Chris and Warren.
The first two months of spring have been drier than normal and November is shaping up to be no different. Hawke’s Bay had 56% of average rainfall in both September and October and now sits on 33% of November’s average with two thirds of the month gone. Some areas in the region are having a particularly dry run, the worst hit being the Heretaunga Plains. It’s had four months of below normal rainfall and November will likely be its fifth. The area has received only 13% of its November average to date.
Spring has not only been dry but also warm. Daytime temperatures were more than 1°C above average in both September and October. Overnight temperatures were more subdued, but still near normal in September and above average in October. The warmth and lack of rain sent soil moisture tracking well below median levels for the time of year and likewise groundwater levels and river flows aren’t meeting monthly averages.
The rest of November may not offer much more rain but ingredients exist that should help beyond that. Sea temperatures are warmer than average around New Zealand and in areas where some of our storms originate, such as the Coral Sea and Pacific Islands. A La Niña occurring over summer is a 50:50 call but the Indian Ocean Dipole looks set for a brief negative phase which is more promising than not for our region. The Madden Julian Oscillation, which can promote tropical storm activity, might be active in the region north of New Zealand in early to mid-December.
Seasonal forecast models suggest summer winds will mainly be from the east to northeast (La Niña-like) due to higher than normal pressure over eastern and southern New Zealand and lower than normal over Australia and the Coral Sea. Stubborn anticyclones are currently keeping rainmakers at bay but the forecasts indicate that the dominance of high pressure will shift southward as we progress through summer and that the area of lower pressure will extend closer to northern New Zealand, enhancing prospects of rain. Near normal summer rainfall could be on the cards therefore… hopefully not arriving in one devastating dump. Temperatures should be toasty for the season, spurred on by the warm seas.
All the best,
Kathleen
Hawke’s Bay Fruitgrowers Newsletter
Jack Wilson
9th October 2024
Post Blossom Thinners
What keeps chemical thinning interesting is the fact it’s just as much an art than a science. A great chemical thinning result is often caused by a plan based on history, a good analysis on the seasonal conditions you have in front of you and plenty of walking blocks. This season we are going into an early compressed bloom with great spring conditions allowing the bees to go hard and therefore the probability of fruit set being high.
With a number of primary thinners been used in those early weather windows we are starting to see their effects, some better than others.
Getting out and walking blocks is critical at this time of year to ensure that any tweaks you make to your plan are based on good observation. Because of the current trend of planting large blocks of single varieties, I am seeing a fruit set gradient across blocks with headland trees and those in rows near adjacent varieties showing heavier set than trees further into the block. Blocks need to be carefully checked for fruit set gradients and the thinning programme adjusted accordingly.
The post blossom thinning window is quite wide so there is no need to panic about getting thinning sprays on if the weather doesn’t allow. Weather always trumps fruitlet stage for secondary thinners and these days we are lucky because we have chemistry for most weather conditions.
Benzyladenine (BA) thinners are not very effective on fruitlets less than 7 or 8mm diameter, irrespective of weather conditions. 10 to 12mm diameter king fruitlet size is the preferred size range and I have also seen good results out of 18 to 20mm diameter fruitlets , due to the tree being under significant stress at that time. The addition of NAA to BA will give you more effective thinning, particularly if you are going in at the smaller fruit size end of the desired range, however do not use BA with NAA on Fuji. BA and BA+NAA is temperature sensitive requiring >18oC for the next 2-3 days post application.
Metamitron is another post blossom thinner with a photosynthetic inhibitor mode of action. It has a wide window of application (6-20mm), with the best effect at 10-12mm. Metamitron has a greater thinning result under carbohydrate deficit favouring conditions, including warm nights, cloudy overcast days, high interfruit competition, shaded trees and general tree stress (waterlogging, frost etc.).
Keep walking blocks and observing, some say it’s the best chemical thinning strategy out there.
HAWKE’S BAY APPLE AND PEAR INDUSTRY INJECTS ALMOST $1 BILLION TO REGION
New research reveals pipfruit export growth is outstripping national export growth
Today, we release the results of a recent study into the economic impact of our industry.
The Economic Contribution of the New Zealand Apples and Pear Industry 2024 tells a great story.
It reveals how our pipfruit industry contributes almost $2 billion of total revenue impact to the New Zealand economy, and what’s more, it shares how the value and contribution of our industry is growing.
At a regional level, this is equally true for Hawke’s Bay.
Hawke’s Bay’s apple and pear industry is the third highest contributor to the regional economy, injecting $991 million of total revenue impact into Hawke’s Bay, according to the research.
With 65 per cent of the nation’s apple and pear plantings, Hawke’s Bay’s pipfruit industry employs more than 6,000 people and makes up 77 per cent of the region’s horticulture revenue.
The report, conducted by MartinJenkins to reveal the economic contribution of the industry to national and regional economies, also found that the industry as a whole had grown its national export value from $347 million in 2012 to more than $892 million in 2023.
The growth in this export value has largely come from increased productivity, investment in high value varieties as well as the diversification of international markets, which means our sector is well placed to further align with the Government’s desire to double export value in 10 years.
However, while you might see a largely optimistic story in your local media, we know that this doesn’t reflect the difficulties the industry is facing.
We know that in the last two years, direct revenue growth has contracted to -0.5 per cent (from +8.2 percent between 2015-2020); we know that cyclone recovery is ongoing; and we know that conditions remain challenging across the board.
But this is exactly why we must use this report to showcase the value of the industry.
We are demonstrating what our industry can achieve when the conditions are.
We will use this new report to further encourage both local and central governments to recognise the value of the industry and work with us to ensure there is an operating environment that is conducive to growth.
With the right settings, the valuable role of our industry can be secured, and we can continue to produce the world’s best quality fruit right here in New Zealand.
So, while you might see a largely optimistic story in your local media, please know we see and recognise the difficulties, and will continue to advocate on your behalf to address these.
Discover key statistics here
Kia ora koutou,
Our teaching at EIT is winding down, with only one course left for the Level 4s, Human resource, which sits well at the end of their study year, looking at employment requirements and leadership skills such as conflict management. These students have completed their plant growth regulator project that they will present to you, and evidence of this is part of the assessment, so please ask some challenging questions. The fruit crop management assessment runs on through thinning time, and they will be gathering data on products used, information on pollination, and ending up with some crop estimation thoughts. Thanks to Garry Burlace from Horticentre for his lecture on chemical thinning, it would be helpful if they can now walk the blocks and listen to your opinion on how your products have performed this year.
Most level 3 students have one course to complete, with harvest and thinning classes over the next few weeks. They have plenty of assessment work to complete, with irrigation and crop health due at the end of this month.
The level 5 fruit production students are on the final stretch of this years teaching. They are completing the labour management course and now have the last of their assessments to hand in.
We had a fantastic visit to the very supportive staff at plant and food to see the root stock and apples variety breeding programs, and an informative visit the L.E.Cooke to see the commercial aspects of tree production. Thank you to all who have given their time to host us and give the students a wider understanding of the industry.
The Post Harvest students are currently working through the Plant and machinery course where they learn about efficiencies, budgeting and developing a CAPEX proposal, not forgetting the OPEX requirements of any new bit of kit may require.
We have had some fantastic industry visits, Thanks to T & G for hosting use and showing use the new pack house in full flow. The box making, delivery, collating and palliating line is truly impressive. We will be visiting Hawk packaging tomorrow to look at the efficiency gains from the tray packing robots. Again a big thank you to all those who host us and give the students the wider perspective of the industry.
The government has announced that horticulture will be supported by apprenticeship boost funding in 2025, but along with all other programs, only available for the first year of study. We are still awaiting information on what fees for 2025 will be, our application for reduced fees, to try and keep them in line with 2024, is yet to be approved.
Kia pai tō koanga
Clare, Steven, Chris and Warren.
We are seeing the influence on our weather of the “Sudden Stratospheric Warming” events that occurred over Antarctica during July and August. The phenomenon has the effect of pushing an unsettled westerly flow over New Zealand, from which Hawke’s Bay can be sheltered at times by the western ranges. The upshot so far is that July had below normal rainfall across the region, reaching 75% of the month’s long-term average. August delivered a near perfect 102% of the month’s average rainfall but the Heretaunga Plains and Northern Hawke’s Bay were two areas that missed out and were below average for the month. The end of September is almost upon us and we have received only 50% of average rainfall for the month. The Heretaunga Plains could therefore clock up three consecutive months of below normal rainfall.
Soil moisture levels are holding up quite well nonetheless, with many sites sitting near median levels for the time of year. Groundwater levels were near or above normal at the end of August and similarly river flows. Air temperatures were balmy in August, especially daytime temperatures which were 1.5°C above average.
A La Niña event is still possible but hasn’t eventuated just yet and is expected to be relatively weak if it does. The Indian Ocean Dipole is expected to remain neutral and not majorly influence our weather. Sea surface temperatures are warmer than usual around New Zealand.
The predicted sea level pressure pattern for the next three months has an area of higher than normal pressure extending over New Zealand from the east and south, which suggests a switch from the current westerly regime to a northeast wind flow. The warm sea temperatures should aid continuation of warm air temperatures, while rainfall forecasts are mixed amongst the forecast models but mostly settle on near normal rainfall over the three-month period. My bike rides in the blustery westerlies have been hard going and borderline wild at times, so I’ll be quietly thankful for a respite.
All the best,
Kathleen
