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The benefits of kelp and seaweed in farming
Liquid kelp is one of the most cost-effective bio-stimulants available to South African growers: rich in trace elements, natural growth regulators and soil-feeding carbon.
Quick answer
What does kelp do for crops?
Where most fertilisers supply only the basic macronutrients, kelp and seaweed deliver a broad spectrum of macro- and micro-elements, vitamins, alginates and natural plant hormones. Together these improve soil chemistry and structure, lift crop quality, and help plants withstand heat, drought and disease pressure.
Crop nutrition
The nutritional benefits of kelp for crops
Kelp is not a substitute for a balanced nutrition programme. It is what makes the rest of the programme work harder.
Better nutrient uptake
Potassium, phosphorus, iron and a wide range of trace elements support faster growth, stronger stems, larger leaves and better fruit set.
Stronger natural defences
Bio-active plant hormones help build more resilient plants, better able to cope with disease, pests and environmental stress.
Improved taste and appearance
Beneficial compounds in kelp improve flavour, colour and overall quality, making produce more marketable and better travelled.
Soil & environment
What kelp does below ground
Kelp is good for crops and good for the system they grow in: soil, water and air.
01
Less soil erosion
Organic matter and alginates promote soil stability and aggregate structure, holding soil in place through heavy rain.
02
More microbial activity
Amino acids, enzymes and natural sugars feed soil microorganisms, driving nutrient cycling and fertility.
03
Fewer synthetic inputs
A renewable, chemical-free alternative that reduces the environmental load of a conventional fertiliser programme.
Yield & resilience
You do not trade yield for sustainability
Used consistently, kelp supports bigger, more even yields alongside better quality and stronger disease resistance.
Bigger yields
Natural growth regulators and micronutrients drive faster establishment, stronger root systems and more productive plants.
Less disease pressure
Polysaccharides and antifungal compounds help crops resist blight, decay and wilt, meaning less damage and less loss at harvest.
Application
Four ways to apply kelp and seaweed
Rates vary by crop, product concentration and growth stage. Get in touch and we will confirm the right rate for your programme.
01
Foliar spray
Liquid fertiliser applied directly to the leaf rather than the soil, for fast uptake and bio-stimulation.
02
Fertigation
Nutrients injected through the irrigation system: efficient, even, and easily scheduled through the season.
03
Soil application
Powdered kelp spread by hand or spreader and worked into the soil to a depth of 15 to 30 cm for best results.
04
Seed treatment
Soak seed in a kelp solution for 6 to 8 hours before planting to improve germination, rooting and seedling vigour.
Is kelp cheaper than conventional fertiliser?
Over a full programme, yes. Kelp is a low-cost input per hectare, and the returns compound as soil health improves, which is what makes it a better long-term investment than a straight synthetic replacement.
Lower input cost
Affordable for most operations, whether used as a concentrate or as a soluble powder.
Better return on investment
Returns come from three places at once: soil health, crop quality and yield.
Longer shelf life
Easier to store and transport than many conventional fertilisers, with less risk of spoilage or degradation.
FAQs
Kelp and seaweed questions, answered
What growers most often want to know before adding kelp to a programme.
Is kelp a fertiliser or a bio-stimulant?
Primarily a bio-stimulant. It supplies trace elements and organic matter, but its main value is improving how efficiently your crop uses the nutrition already available.
Liquid kelp or kelp meal, which is better?
Liquid suits foliar and fertigation programmes and acts quickly. Meal or powder suits soil building before planting. Many growers use both.
How often should kelp be applied?
Regular low-rate applications outperform occasional heavy ones. Most programmes apply at key growth stages and ahead of predictable stress such as heat or flowering.
Can I mix kelp with other products?
Kelp tank-mixes well with most foliar nutrition and with fish hydrolysate. Always run a jar test first, and avoid strong oxidisers.
Does kelp help during drought?
It is widely used as part of a stress-mitigation programme. See our guide to dealing with drought in Southern Africa.
Can I export or import kelp hydrolysate?
Yes, we supply bulk liquid kelp to distributors internationally. See importing liquid fertiliser from South Africa.
Ready to try kelp on your farm?
Whether you farm two hectares or two thousand, we have the products and the agronomy support to get you started.
Call us+27 33 347 2893
Emailadmin2@zylemsa.co.za
Visit usUnit 20, 3 Cascades Crescent, Chase Valley, Pietermaritzburg, KZN, 3201
Explore the range
Other raw materials we work with
Kelp is one of several biological raw materials behind our formulations.