Water, Water Everywhere

Jennifer Calhoun
Maybe you’ve seen it before: The germination on your trays looks great. Everything is going well in Stage 2, then the plants start looking yellow and chlorotic. You think they seem a little hungry, so you feed them, but it doesn’t help. Soon, plugs start dying one by one and you’re left wondering, “What happened to that great germination I just had?”

You might be experiencing the effects of overwatering. Improper watering can have devastating effects and result in losses of up to 15% in some crops.

Here are a few tips from the experts at Benary on which crops are most susceptible and the tell-tale signs to look for.
Crops that are most susceptible to overwatering:
Dusty Miller

What to look for:

Water sitting on top of the plug. This is probably the most obvious sign, but often overlooked.
Algae on top of the soil. Usually a sign of overwatering, but can also be caused by improper watering when water cannot move freely from the top of the plug to the bottom.
Chlorotic, yellow foliage. Because the roots are saturated, they cannot take up nutrients properly. Fertilizing will either have no effect or could make the yellowing worse.
Brown roots. When roots are saturated for a long time, there’s no airflow to keep them white and healthy looking.
Begonia seedlings also may not root in when you use too much water pressure. You’ll notice they move around on the media even though they seem buried.

Pictured: An overwatered portulaca plug tray.

What can you do?

• Consult your Benary Culture Guide for the specific watering requirements of your crop.
• Look at the roots of your plugs regularly. They will help you identify the problem early.
• Check to make sure the EC is within the suggested guidelines.
• It’s critical to begin a good wet-to-dry cycle to prevent algae growth and help with the uptake of nutrients. What day to start the wet-dry cycle depends on the crop, but it’s usually in Stage 2.
• Increase the amount of horizontal airflow. This will help dry out the media and allow for better nutrient uptake.

For more information, visit or contact your Benary Sales Rep. GT 

Jennifer Calhoun is Marketing Specialist for Ernst Benary of America.