How to water your vegetable garden so that you do not need to water all season long? Most watering in our vegetable garden has one simple goal: to establish young plants. Of course, there are exceptions to this, in the case of very dry and hot times, container gardens, and greenhouses need to be watered.
The need for water in the vegetable garden
Before we jump into the how-to water your vegetable garden, let’s consider the need for water in the garden. Garden plants are not water plants. Even though we talk about watering, plants actually need moisture, not water. But since water creates moisture, hence we water the garden.
However, when considering moisture you will evidently notice that different gardens would keep moisture very differently. There is no “one fits all” approach to water a vegetable garden. We have grown gardens where we’d not water at all, and also where we’d water quite regularly.
A raised bed or a garden on a hill will dry out quicker than a garden in a lowland. Wind and sun exposure also play a role. And of course, different soil will keep moisture differently.
To find out if your garden needs water or not, a moisture tester is handy. You can also dig a small hole with a hand spade. Observe your soil. If the soil under the surface is drier than on top, you need watering. If the soil gets moister with depth, watering might not be needed. After some practice, you can use a finger to find out. And with even more practice, you will start to see it on your plants if they need water.
Speaking of plants. Plants have different moisture needs. Some like it constantly moist, others prefer to dry between watering. However, plants that are overwatered often look just the same as those that are underwatered. Checking the soil is always more reliable, especially for a beginner gardener.
Generally speaking cold weather crops like brassicas, greens, and peas like more water. They naturally grow during the rainy cool season. Of course in a cold climate, we grow them during the summer and they benefit from watering.
During hot dry weather, these cool-weather crops also benefit from shade cloth. A frost protection blanket is great for that. If used for shade, make sure there is air circulation under the blanket.
Also, shallow-rooted heat-loving plants like cucumber, squash, tomatoes, etc will ask for water during dry and hot weather. This brings us to our first tip on watering.
1. Water deep
The first and most important thing to know about watering is that you want to water plants deeply. What do I mean? You want the water to go deep, not just moisten the surface and let it evaporate.
Plants develop roots according to the moisture available. Some plants are naturally more deep-rooted (like carrots), others are more shallow-rooted (like tomatoes), but all plants will develop deeper roots if all the moisture available is down under them.
If you water plants little by little, plants will not look for moisture deep in the soil but will develop shallow roots. Shallow rooted plants will always ask for moisture from above and look dry and limp every single day. The result is a very stressful growing season. To avoid frequent watering, water plants deep from the beginning.
At planting, water the hole to give the roots a signal that moisture is under them. Try also to plant seedlings with deep roots in mind, pointing the roots downwards. Now water very well, and leave the plants alone for a few days up to a week. The roots will find moisture and grow in the right direction.
To establish young plants, water them thoroughly once or twice a week, depending on the weather. If you have a big garden, water one row or one bed at a time, and do it well. It is much better to water less frequently but deep than often but shallow. Deep watered plants will establish a root system that will not depend as much on water from above, and you can have your summer off.
This is also true if you get frequent but light rain in spring. Make sure still to water young plants deep.
2. Water with stagnant water
To water with a hose directly from the water faucet is convenient, but is not the best for plants. City water may or may not kill beneficial bacteria and life in your soil, but it is way too cold for your plants.
Make sure to have a water reservoir for watering plants where water can warm up and the chlorine in it evaporates. We use water barrels to gather rainwater, or we fill one with tap water as needed if there is no rain that would fill them.
In a greenhouse, a water tank can look good, help with temperature regulation, and also be a great reservoir for watering plants. Refilling the reservoir with cold water during the day helps to keep the greenhouse cooler.
3. Do not drown plants
We already established that plants only need moisture, not water. We water plants to give them moisture. You want to water plants deep and thoroughly without drowning them.
Drowning will not happen by watering deep, but by watering too often. Allow the soil to dry somewhat in between watering. This is especially important for container gardening. Too much water is way more dangerous than too little.
4. Apply water at the plant root base
There is no need to water the whole garden. It is better to water directly at the plant root base. This can be done with a water can or a cup, and even with a hose that has a Showerhead Watering Wand.
It is helpful to make a little barrier around the plant to contain the water. So it can stay at the base and not flow away.
Many plants (especially those from the squash family) do not like to get wet, watering all over them can even harm them. During a hot day, cold water can burn the leaves.
If you water plants individually, you can see better if a problem needs to be addressed. A plant that grows well, drinks well. Especially for container gardening, it is good to observe the plant and the soil. If one plant is moist and all others are dry, you know there is a growing problem. Do not water all the plants alike, water each as needed.
5. Water during the cooler time of the day
When is the best time of the day to water your vegetable garden? The best time is when you have time to do it. However, less water will evaporate if you water during the cooler times of the day.
It does not really matter if you water early in the morning, or at night. We usually water the garden if needed in the evening, and the greenhouse in the morning. Outside the garden stays moist longer if we watered at night since wind and sunshine dry it out quickly. In the greenhouse night, watering can lead to too much moisture.
If midday is the only time you have to water the garden, be especially careful to use stagnant water, that is not cold and water the soil, not leaves. As we already mentioned leaves can burn.
Mulching helps to keep moisture in the soil so watering is not needed as often. In very dry areas wood chips work best. However, any mulch can work. I have even seen tomato growers who cover the soil around the plant with newspapers. It works.
Mulching conserves moisture and prevents weed growth, insulates the soil in cold weather, keeps the soil cool in hot weather, and, if using organic material, enriches the soil.
If you don’t have enough material to cover the whole garden, cover at least the base of a plant. Here we used comfrey, but grass clippings and even seedless weeds work. The soil will stay moist longer.
If you have a watering tip we missed, please share it in the comments. Remember, we are all learning here together.