Vine Decline Syndrome
Kiwifruit vine decline syndrome (VDS) is becoming a bigger problem in orchards across New Zealand.
Scientists are still studying what causes kiwifruit vine decline, including possible pathogens. But right now, it looks like the health of the vine itself plays a big part. That means there are things you can do now to help reduce the impact of VDS.
Stressed vines are more vulnerable to vine decline, reduced yields, and in the worst cases, complete collapse.
Keeping a close eye on vine health will help you improve fruit quality & vine health and reduce production costs.
What to Look for
We recommend you walk through your orchard.
or find a high vantage point where you can get a clear view over the canopy.
Look out for any gaps, yellowing foliage, or premature leaf drop.
As you can see in the image above, parts of the canopy are yellow, indicating poor leaf health. This orchard may experience early leaf drop and these areas should be checked carefully for signs of stress. This orchardist plans to use Primazest and Agrizest next season to reduce stress and maximise returns.
On the ground, inspect the leaders and trunks for signs of swelling, cankers, dieback, or other irregularities.
Also, take note of overall leaf condition.
Premature leaf fall allows light to penetrate and, where leaf fall was very early, grass has grown.
Check the main leaders. Focus on older leaves which will show signs of breakdown first.
Standard management: note the leaf necrosis.
The symptoms of vine decline will be easiest to spot in green kiwifruit where necrosis follows a specific pattern between the veins. Young leaves may still look healthy:
Advanced yellowing in G3 Gold Kiwifruit
Young grafts may also be affected:
Advanced leaf necrosis
Vs healthy vines, treated with the Primazest programme only. no copper, or antibiotics post bud-break:
Necrosis in Hayward Green Kiwifruit
Many growers assume this to be the result of nutrient deficiency and apply more foliar nutrients and fertilisers.
Unfortunately this only aggravates the problem in both producing vines and in newly grafted orchards.
Read more about fertiliser use on kiwifruit orchards here.
So what should you do?
Only apply fertilisers when soil tests show a deficiency. Don’t aim for “high fertility” without evidence.
Test your leaves before using sprays or foliar feeds and only use them if a deficiency is found.
Be careful with copper: stop using it after bud burst and try to avoid building up copper in the soil where it can become toxic to your vines.
Stop foliar nitrogen sprays unless tests show a clear need and wait to add potassium until soil tests say it’s needed.
Consider the Agrizest & Primazest programme to help your vines cope with stress, improve yield, and enhance fruit quality.
Apply foliar magnesium only when soil potassium is high.
Remember nutrients interact - too much of one nutrient can cause deficiencies in others (e.g. high nitrogen can limit uptake of boron and potassium). You can have too much of a good thing.
These steps are best practice, crucial to sustaining healthy vines, strong crops, and your long-term orchard profitability.
With climate stresses adding new challenges, it’s more important than ever to take a careful, science-informed approach.
Check your soil and leaf test results
And
If you haven’t already, consider adding Primazest (to support early season growth) and Agrizest to your programme to help optimise vine health and fruit quality.
You Can Manage This
Agrizest and Primazest programme, no copper applied once in leaf.
Now’s a good time to review your fertiliser programme—remember, even beneficial inputs can be overdone.
Check your soil and leaf test results: Aim for the medium range, not the high end.
Walk your orchard, look for signs of stress and take proactive measures on our orchards to keep your vines healthy and productive.
Read more about fertiliser use in kiwifruit orchards and the potential effects of over-fertilisation on fruit quality here.
And in young, grafted orchards:
Primazest programme only.
No other nutrient sprays or applications of fertilizers.
NO copper or antibiotics post bud break.
This orchard has been using the Primazest & Agrizest programme for the past 15 years.
No foliar nutrient sprays, copper or antibiotics are applied post bud break.
