Plan the perfect garden with our interactive tool →

Watermelon Plants & Salt Water

...
watermelon image by ewa kubicka from Fotolia.com

According to the National Watermelon Promotion Board, the United States is the fifth largest producer of watermelons in the world, with the states of Georgia, Florida and Texas leading the nation. Watermelon is an even more important crop in the arid lands of China, Turkey and Iran, where salty ground water is prevalent. Watermelons prefer loose, well-drained, non-saline soils, but are able to tolerate some salt exposure during cultivation.

Salt and Plant Nutrition

Salt dissolves into water, separating into positively charged sodium (Na+) and negatively charged chlorine (Cl-) atoms. Sodium is close enough chemically to potassium to fool plant cells into absorbing it, thereby blocking potassium from where it is needed. Potassium plays a critical role in dozens of cell functions related to growth, mostly by causing enzyme structures to reorganize into their reactive forms. Growth and root development slow as a result of sodium poisoning.

  • According to the National Watermelon Promotion Board, the United States is the fifth largest producer of watermelons in the world, with the states of Georgia, Florida and Texas leading the nation.
  • Sodium is close enough chemically to potassium to fool plant cells into absorbing it, thereby blocking potassium from where it is needed.

How Salt Exacerbates Drought Conditions

Watermelon is often grown in dry areas because, contrary to their name, melons don't require a lot of water in cultivation. In fact, too much water dilutes the sugars in the fruit, resulting in a less tasty product. However, where salt is present, crops become thirstier as osmosis pulls water out of their roots to balance with the salt. Worse, since dry areas can't count on rainwater to hydrate the fields, open irrigation often results in much of the irrigation water evaporating, and thereby concentrating salt before it gets to plant roots. Watermelon is also a very shallow-rooted plant; frequent watering is needed because fluid seeping into the soil soon descends beyond the useful reach of the plants.

How Watermelon Plants Cope with Salt

Water loss triggers a defense response in watermelon plants. Leaves close their stomata to reduce more water loss through transpiration. The plant produces osmolytes to stabilize cell membranes and stop water loss through osmosis. These measures are meant to be only temporary, as they also halt nutrient transport within the plant and carbon dioxide intake, which plants need for photosynthesis.

  • Watermelon is often grown in dry areas because, contrary to their name, melons don't require a lot of water in cultivation.
  • These measures are meant to be only temporary, as they also halt nutrient transport within the plant and carbon dioxide intake, which plants need for photosynthesis.

Increasing Watermelon Yields in Salty Conditions

Since sodium competes with potassium in plant cells, growers coping with saline soils fertilize heavily with potassium to make it more prevalent and therefore available to their crops. Evaporation of ground-sourced irrigation water increases its saline concentration, so preventing as much water loss as possible is important. Drip irrigation systems virtually bring evaporation to a halt, as the water is delivered directly to the base of the plants, where it can trickle straight down to the roots, shielded from the energy of the sun by the leaves of the plant.

Salt and Watermelon Fruit

Watermelon absorbs some sodium and chloride atoms from saline solution, which end up in the fruit. Water also ends up in greater quantity in the fruit, with the result that the melons are juicier and have fewer solids than non-saline yields.

Through careful cultivation, research has shown that watermelon is moderately resilient and able to produce adequate yields up to a certain threshold of saline exposure, but if salt levels are too high, the harvest and plant vitality are adversely affected. The nutrient displacement, water loss and drop in photosynthesis all take their toll with stunted growth, yellowed leaves, little or no fruiting, and even plant mortality.

  • Since sodium competes with potassium in plant cells, growers coping with saline soils fertilize heavily with potassium to make it more prevalent and therefore available to their crops.
  • Through careful cultivation, research has shown that watermelon is moderately resilient and able to produce adequate yields up to a certain threshold of saline exposure, but if salt levels are too high, the harvest and plant vitality are adversely affected.

Related Articles

The Effects of Salt Water on Tomato Plants
The Effects of Salt Water on Tomato Plants
How Salt Tolerant Is a Bean Plant?
How Salt Tolerant Is a Bean Plant?
How Table Salt Affects Plant Growth
How Table Salt Affects Plant Growth
Why Do Watermelons Split on the Vine?
Why Do Watermelons Split on the Vine?
What Happens to Roadside Plants When Salt Is Used to Melt Ice on Roads?
What Happens to Roadside Plants When Salt Is Used to...
The Effect of Carbide in Fruit Ripening
The Effect of Carbide in Fruit Ripening
What Foods Are Grown in Spain?
What Foods Are Grown in Spain?
The Effects of Urine on Tomato Plants
The Effects of Urine on Tomato Plants
Effect of Salinity in Soil on Pea Plants
Effect of Salinity in Soil on Pea Plants
What Kinds of Fruit Grow in the Amazon Rainforest?
What Kinds of Fruit Grow in the Amazon Rainforest?
How to Grow Tomatoes in Sandy Soil
How to Grow Tomatoes in Sandy Soil
The Effects of Roundup on Food Crops
The Effects of Roundup on Food Crops
The Usage of Epsom Salt & Ammonia in Tomato Gardening
The Usage of Epsom Salt & Ammonia in Tomato Gardening
Nutrients Needed for Hydroponics
Nutrients Needed for Hydroponics
What Can You Plant With Okra?
What Can You Plant With Okra?
Garden Guides
×