HOW TO WATER YOUR GARDEN
Watering is one of the most meditative gardening tasks. You’re giving your plants their lifeblood while you admire, inspect, worry over, harvest from, and revel in your garden.
It is best to water less frequently and more deeply. But that means watering slowly. It can take several minutes to soak even a small root ball. Automated irrigation systems’ clocks will take a little programming and then seasonal adjustment for watering duration and frequency. Watering thoroughly at planting time and in the first couple of months afterwards is crucial.
Soil conditions influence watering
Your soil conditions will determine how frequently you need to irrigate. Get your hands into the dirt all over your garden and make mudpies. The ones that fall apart immediately are made of sandy or gravelly soils. The ones that cling nicely together but can crumble like an unbaked cookie are made of loam or silt. The ones that are sticky, that you can really smack into a paddycake and, are, well, clay-like, are made of clay soil. Sandy, rocky, or gravelly well-drained soils require more frequent watering to serve your garden plantings. Sticky, heavy clay soil retains moisture and thus requires less watering, but it poses two problems: It’s harder to re-wet once it’s dried out, and it can stay so soaked that it drowns the roots of your plants. Loam or silt demand less of you: less-frequent watering than sandy soils, and less worry about drowning your plants.
Buy a hose
If you don’t have a hose that delivers water to all of your garden, get one. Consider installing an automated irrigation system. But you’ll still want a hose: for planting, showering off dusty plants, and spot-watering.
No matter how drought-tolerant your plants, you’ll need to water your garden. Maybe not every day or every week, but you’ll want to find a rhythm that changes by the season. The sun accelerates photosynthesis, the which requires water, and dry air accelerates transpiration, a fancy word for plants’ leaves losing water through their pores.
Watering is key at planting time and afterwards
When you plant, thoroughly soak the planting hole and then the planted rootball. (Thorough soakings and follow-up dousings are less important for planting agaves and cactus and many other succulents.) For the next couple of months, you’ll want to make sure those new plantings get a good soaking every week (depending on your soil type), or even more if it’s hot or windy.
Container plantings will require more-frequent and thorough watering. Root space is limited and potting mixes drain efficiently. Even drought-tolerant plants like olives will demand more of your attention, though the toughest succulents like agave americana will endure long stretches of dryness. A large plant in a small pot needs more frequent waterings than a plant with a large pot with lots of room for roots. A saucer under the pot can act as a reservoir for a few days – as long as the water in the saucer stays in contact with the drainage holes.
These plants have lowest summer water needs:
Cactus (besides jungle cactus); agaves & furcraeas; succulent euphorbias; many aloes; eanothus, manzanita, grasses, annuals, Guadalupe palms, iris, dudleyas, and eriogonum; leucadendrons, proteas, olive, rosemary, bearded iris, banksias, Mediterranean fan palms; bulbs like daffodils, freesias, and naked ladies
Plants that need moderate water:
Ornamental grasses; cordylines, coprosmas, phormiums, tea trees; some penstemons, calylophus, pelargoniums, artemisia, kangaroo paw, crinum, and certain other perennials; echeverias, sedums, kalanchoes, and many soft succulents; pindo, windmill, and queen palms; bromeliads; many conifers; oaks
Plants that need plentiful summer water
bamboos; many palms like pygmy date, king, lady, and chamaedorea; Japanese maples, magnolias and many other deciduous trees; ferns; redwoods; many summer annuals; acorus, asarum, ligularia, and lots of other perennials
Good-looking gardens need water! Oh, are we repeating ourselves? It’s because one of the key causes of plant failure is watering failure, especially in the planting and establishment phase, but also in the late winter and spring when rains cease. If you’re very planful and lucky – by planting natives in the fall before a classically rainy winter, for instance – you may only need to water the first couple of weeks after planting. But that’s the laudable exception.
In some years, winter rains do not provide enough moisture to serve newly planted plants. It’s important to supplement those rains with irrigation when they fail. Winter is the time of the year when these plants must have moisture to thrive and to survive the following summer drought. Get attentive to your soil and your plants so you can respond to your garden’s need for water. You’ll be richly rewarded.