Late Season Strawberry Crop Nutrition Strategy
In areas that are still producing high volumes of strawberries at this time of the year, like the Watsonville-Salinas region, choosing a balanced fertilizer program according to the current crop stage is fundamental for achieving higher productivity.
There are five key nutrients that have specific roles in improving yield and quality during fruiting stages of strawberries:
Potassium – plays a key role in maximizing fruit quality by increasing fruit sugars, acidity and improving taste. Potassium improves water regulation within the plant, stress tolerance, transport/accumulation processes and boosts strong growth. The strawberry fruit accumulates more potassium than all other plant organs combined. Therefore, sufficient potassium needs to be supplied all the way from flowering through harvest.
Calcium – is essential to maintain fruit integrity, health and a longer shelf-life, with reduced fruit damage when handling. In addition, calcium helps improve tolerance to diseases and salinity, maintaining good, stress-free growth. Peak demand is during flowering and fruit formation and although many of our soils have high total calcium, this is frequently not enough for plant and fruit demand due to its limited solubility and plant availability.
Calcium deficiency symptoms on leaves
Nitrogen – particularly nitrate forms – in limited quantities to balance other nutrients during flowering and fruiting – will maintain taste and acidity without encouraging rots. Too much nitrogen results in excess plant vigor and a larger canopy. This leads to delayed ripening and malformed fruit, a greater incidence of disease and lower soluble solid content, flavor, firmness, and a reduced shelf life.
Excessive nitrogen increases plant susceptibility for disease and fruit rotting - Botrytis
Phosphorus – delivers energy to the plant and is particularly important for flowering and higher fruit production.
Boron – also plays a key role in fruit quality and has a direct effect on membrane integrity, maintaining cell wall structure. Poor boron supply leads to smaller, malformed fruit.
Crop Nutrition Tactic
Avoiding high rates of nitrogen after mid fruit development and ensuring a high calcium and potassium status in the fruit, will help maximize fruit production while minimizing the impact of biotic and abiotic stress.
During flowering and fruiting, the supply of ammonium should be avoided, especially during high temperatures. Research shows that when ammonium nitrogen exceeds 10% of total nitrogen in combination with high temperatures lower yields can result (Lieten, 2003). YaraLiva® CN-9® is the premium nitrate and calcium source to fertigate strawberries at this stage. Nitrate nitrogen supports fruit firmness and shelf life, as it stimulates the uptake of calcium.
YaraTera® Nitrakal™ is a liquid formulation of potassium nitrate and calcium nitrate, which provides N, K and Ca at the right ratio to help strawberries achieve higher marketable yield and better fruit quality.
Foliar fertilizer application is an effective tactic to address immediate nutritional needs, especially at the end of the summer, when stressed crops show reduced ability to uptake nutrients from the soil. Foliar sprays apply nutrients directly to the plant and rely on leaf and fruit absorption.
Foliar phosphorus along with potassium and magnesium from YaraVita® MAGPHOS™ provides a quick-acting source of energy that keeps the plants at a high level of production. YaraVita MAGPHOS provides the energy for heightened photosynthesis which also help the plant overcome periods of stress.
Foliar calcium will enhance fruit firmness and quality. YaraVita® CALTRAC™ is a high analysis foliar material to be applied early in the fruiting cycle. You can also switch to YaraVita® SENIPHOS™, which combines soluble calcium with high energy phosphorus for color development without fruit softening.
Reach out to your local Yara Agronomist to learn more about the role of specific nutrients in strawberries and how to best utilize these products in your comprehensive nutrition program.
Yara CheckIT™ App
Use Yara's CheckIT App from your mobile phone to assess the status of your strawberry crop. Download it from your app store.
For more information, contact:
Sebastian Korob, Crop Manager
sebastian.korob@yara.com
(424) 645-4047
Patricia Dingus, Regional Sales Manager
patricia.dingus@yara.com
(805) 765-7446
Eddie Muro, Sales Agronomist
eddie.muro@yara.com
(805) 215-6981
David Morgan, YaraVita Specialist
david.morgan@yara.com
(559) 977-0233
