How Much Water Do Vegetable Gardens Need?

We are so grateful to have gotten some measurable rainfall in Louisville, KY this week! There truly is no substitute for good old fashion rain in the home garden.

It’s been a HOT summer with temperatures in the 90's and heat indexes in the 100's. Thank goodness for irrigation systems, city water, and of course RAIN water.

Fruits, vegetables, and herbs are heavy drinkers, ha, and need consistent watering. If not, they can develop a myriad of problems. 

Inconsistent watering in a food garden can lead to: Blossom End Rot on tomatoes and peppers; plants drying out and burning up entirely; stunted growth and development; and unworkable soil - to name a few.

Here is a good metrics on water requirements for edible plants:

Most food crops need one inch of water per week in 60 degree Fahrenheit weather.

For every 10 degree rise in temperature your plants will need an additional 1/2” of water.

In the 70’s you’ll need 1 1/2” of water.

In the 80’s they need 2” of water.

In the 90’s they need 2 1/2”.

Heat index’s in the 100’s need 3” of water.

If the weather is exceptionally windy your plants will dry out quicker, thereby demanding more water.

Tiny emerging seedlings need the soil surface to stay moist during this crucial stage.

Larger plants need a deeper drink of water to draw from throughout the day.

If you are relying on rainfall to meet your watering needs, be sure to buy a rain gauge. Rain gauges measure the amount of rainfall in your area. Place it directly in your home garden for most accurate readings. 

Always check the soil by hand when in doubt. Reach down into the root zone (about 2-3" deep) to determine soil moisture. The soil surface will always be more dry than the root zone due to direct sun and wind. 

Water when dry! Best to water in the mornings before the heat of the day peaks. Water low to the ground so that the roots can find it easily. Use a minimal to medium pressure while watering.

Do not water the foliage because vegetable plants do not absorb water through their leaves. Instead, always water at the root zone. Best to avoid splashing water onto the leaves. Never water with a high pressure hose - this will gush soil over the leaves and could damage seedlings.

It's difficult to measure water by a garden hose or water can. This will take practice and attentiveness to how your plants and soil respond to watering.

If the ground absorbs the water quickly, the soil was dry. Once absorption slows you can move onto the next plant.

If water stays on the soil surface, the ground most likely has adequate moisture content.

Also consider utilizing a drip irrigation system on a timer. This will eliminate lots of worry about timing and consistency. Our company will install a system for you - please reach out.

Thanks for reading with your local horticultural experts!

PS- It’s not too late to start your Fall Gardens. Fall Gardens in Kentucky start in July and August. Think: carrots, beets, radishes, lettuces, spinaches, turnips, cabbage, broccoli, cauliflower, kale, and garlic!

Book a Garden Consultation thru ediblegardensinc.com or call today to learn more at 502-648-8718.