Gardening Basics: Watering

Tending & Training

The job of deciding what to grow is done. Planting is done (at least for now). This is the time when I find myself stealing looks at what’s taking root as though, if I stop and stare long enough, I’ll witness the act of growing first­hand. And somehow I always do, although it happens in a collection of moments and over the course of days.

Gardening Basics

Smart Watering

How much water is enough? Touch the soil and look and feel under the soil surface. If it looks wet or feels wet, then you’re likely in good shape. If it’s dry an inch or more down, it may be time to water. Plants are also good at telling us when they’re thirsty by how they appear, taste or react to their environments. In general, when plants don’t get enough water, they become stressed, leaf tips may burn and turn brown, they’re prone to disease, growth is stunted, and fruit and leaf development is poor. Leaves may also feel dry and crackly, while the leaves of lettuces and other leafy greens become tough and bitter — plus they’re more likely to bolt.

Too much water can lead to similar symptoms. Plant roots may rot or starve from lack of oxygen, causing leaves to wilt, turn yellow or drop, even when soil feels damp to the touch. Above all, fruit loses its flavor. And those cracks you sometimes see on tomatoes? They’re caused by inconsistent watering.

The Best Way to Water Plants

What’s below is also above. In order for lush, beautiful plants to grow above the ground, they need to develop lush, beautiful roots below it. Water with the root zone in mind. Are you growing seedlings or lettuces with shallow root systems, or tomatoes, whose roots run deep?

Water deeply using the slowest delivery system possible. This will wet the entire root zone from top to bottom and beyond, encouraging roots to explore. The healthier the root system, the healthier your plants.

Give plants water when they need it. Weather, climate and season affect the amount and timing of watering, along with wind, sun and humidity. It can change from one day to the next. Keep an eye on plants, and check soil moisture by pushing a finger underground or taking a look (without disturbing roots). In general, if soil is dry an inch or more down, water. This varies from plant to plant. Drought-tolerant plants like rosemary prefer soil to dry out between watering, while tender herbs such as cilantro tip over when soils aren’t kept reasonably moist.

Morning is the best time to water. This gives plants time to dry out before the sun drops, decreasing the spread of waterborne diseases like leaf spot or blights. It also helps manage slug and snail populations. That said, if plants are wilting or look stressed from intense heat, give them water no matter the time of day. Shading certain plants such as greens may also be necessary.

Cover crops, interplanting and mulch all keep soil moisture from evaporating. Apply mulch or coarse compost to cover bare soil, and interplant by pairing taller and shorter plants. Grow edible flowers or other companion plants to reduce the amount of bare soil. 

Water at soil level. If you can set up a drip or soaker hose system, do it before you plant. Not only would all my plants die if relegated to hand-watering (because I don’t have the patience for it), but it’s also not the best delivery system. Have a hose with an adjustable nozzle or wand handy, of course, but save it for emergency watering. If you must use a sprinkler, remember to water in the morning for best results and the least amount of evaporation.

When to Hand-Water

I have some longtime gardening friends who swear by hand-watering. They say it’s the only way to really get to know your plants. You just need to consider the time involved, how plants are watered when you travel and how to water plants like tomatoes that prefer water delivered at soil level. Direct-sown seeds and seedlings also benefit from light hand-watering (see page 218), as do plants that are stressed or wilting due to intense sun.

Watering Systems

A well-planned drip or soaker hose system with an irrigation timer takes the worry out of gardening and reduces your time commitment. There are simple setups that connect to a spigot and can be run along decks or patios, and more elaborate systems for larger gardens. Once they’re in, they’re easy to care for and modify as needed, whether you’re adding micro-spray heads for seedlings, single-stream heads for planters or a drip line for beds.

An olla is an unglazed, low-fired clay vessel that’s buried underground near plant root zones. Water wicks through the walls of the pot and into soil as it dries out, naturally delivering water as it’s needed.

Fill them from the top every few days and that’s it. They’re especially handy when gardening in larger planters.

I use nanny pots to water planters and other small containers that I would otherwise hand-water. If you’re away for a long weekend or simply want to guarantee plants are getting the water they need, fill a bottle with water, flip it over, and push the open end into the soil. The soil will seal the opening, and as with an olla, water will flow from the bottle as the soil dries out.

Self-watering containers operate on a similar principle to ollas, wicking water held in storage into soil. You can make your own or buy them ready made.

Bottom-watering systems are my method of choice when it comes to watering seeds, seedlings and newly potted up transplants. Place seedling pots or flats in a pan of water, and water will wick up through the soil.