More dry weather

After a wonderfully wet spring, the spigot has turned off. We haven't had anything more than a sprinkling of rain since early June. I'm trying to deeply water the vegetable garden at least once a week (and avoid the temptation to water a little bit every day), but it's hard to keep up, with high afternoon temperatures and sunny days.

The goldfinches, brown thrashers, squirrels, and others are depending on the bird bath for water, while the mystery woodchuck is becoming more interested in well-watered squash leaves. It's hard to be too annoyed; there's certainly no succulent fresh growth out there, aside from what's being watered.

The U.S. drought monitor is still showing that we're OK (that's good) and the long-term projections are fine, so this is just a normal LONG droughty spell. But definitely even native drought-tolerant plants that have been recently added (perennials in the last year, and shrubs and trees in the last couple of years) and all of the water-dependent vegetables and container plants need water.

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Waterwise gardening

All the rain last week (hooray for that) meant lots less time outdoors (since it was pouring) and in the garden (actually being back at work is the main reason). But shifting from home garden thinking to work garden ideas isn't too much of a contrast -- it all blends together in how I think about plants, gardening, ecology, environmentally-friendly approaches to gardening, and observing and learning more about nature.

I've been thinking quite a bit this week about sustainable gardening, and what waterwise gardening in our climate really means. Talking this week with my colleagues about updates for our xeriscape garden has me mulling over my approach to sustainable gardening.

I guess because my first interest in plants was those living in 'wild' landscapes that were native to the Texas Hill Country where I grew up, followed by a fascination with weedy species from a summer spent with my family in upstate NY (and visiting frequently in NYC) as a young teenager, and fortified by the tremendous plant diversity in California, where I studied plant ecology as a graduate student, I'm looking at our home landscape/garden with an ecologist's eye to plant behavior and needs.

The standard (US) horticultural recommendation of an inch of water a week sort of seems nuts to me. Is this a lawn thing? My pampered vegetable garden, well, yes, maybe, but our trees, shrubs and perennials (mostly native or tough) will happily get by on a lot less water. Uh, what about all the plants out there in the 'wild'? No one's watering them.

And we certainly DON'T need an irrigation system to successfully garden, even in times of drought.

I think being a waterwise gardener means choosing plants that can withstand dry spells, and flourish without lots of supplemental water (I wrote this in a post last September and this in October). Here in the SE (United States), we can grow lots of great plants that fit that description. Many of our native plants are prized in Europe as normal landscape plants, so this doesn't mean our palette is restricted to cacti and succulents.

Beth Chatto's gravel garden in East Anglia, England (20 inches of rain/yr)

She uses lots of Mediterranean natives in this garden.

Long hot summer dry spells (3-4 weeks) are not uncommon here in the Southeast, so native plants exposed to these conditions (those that don't live along streams,rivers, in floodplains, or in the mountains) have various adaptive strategies to cope, either through different types of tolerance mechanisms or avoidance (by being dormant). Clues to drought-tolerance come from native habitat (grasslands, prairies, dry woods, shallow soils, rocky slopes, etc.), plant habit (deep tap roots or fibrous storage roots), leaf color and texture (gray leaves are reflective, waxy or thick leaves are water-loss resistant).

What really gets me cranky is our American/Southern focus on lawns. In our home garden, we have perfectly nice areas of Zoysia lawn, established many years ago, and greatly diminished in size since we moved in. They never get a bit of supplemental water from us, nor any fertilization, aeration, de-thatching or anything else resembling 'lawn care.' The clippings are left to decompose and renourish the lawn. The lawn patches that are most exposed to sun and on shallower soils have suffered during the drought, turning totally brown. But the rain last week has stimulated regrowth of tender young shoots, so maybe that area isn't ready to be turned into raised beds after all. Darn!

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Drought and Waterwise Gardening

We had an inch of rain this week, thank goodness, since we hadn't had anything since mid-September, but I'm continuing to notice what plants are doing well in this droughty fall, following a brutally hot and dry August.

I attended a waterwise gardening symposium in Athens at the State Botanical Garden of Georgia recently, and the depths and extent of the drought we're in here in the Southeast became ever more evident. I'm certainly rethinking my approach to the challenge; I don't think my fellow participant is on the right track, when she pointed to an aloe plant on the lunch table, and said, "this is what we need to grow," nor that Mediterranean-style gardening or High Desert gardening is the answer either, but we do have a whole range of exceptional native plants with deep roots that are able to withstand long periods of drought in summer. Mix in a few of those Mediterranean plants and high desert plants that can tolerate our heat and humidity in summer, and you've got a great group of plants to work with.

Personally, I think we'll need to phase out the temperate Asian plants (Hostas and Hydrangeas) that need regular summer water beyond what we ever normally get -- this is life support, not gardening. And watering lawns and turf is just not necessary. Our Zoysia lawn areas went dormant, developed brown patches in the shallowest soil areas, but after the one drenching rain we received in mid-September, recovered quite nicely.

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Waterwise gardening

In this summer of extreme heat, and severe drought here in South Carolina, it's hard NOT to think about drought-tolerant plants. We have tried to establish a low-water use landscape, but that doesn't mean no water, especially with recently planted perennials, shrubs, and trees.

We've both gotten really tired of dragging the hoses around to water these young plants that we don't want to lose, but anything planted this year needs water to survive the high temperatures, hardly any rain, and too much wind conditions that we've had. Our plants would normally thrive, after establishment, on normal rainfall, but rainfall this summer has been anything but normal, and even the toughest drought-tolerant perennials have wilted in the late afternoon sun. Trees, with their much more extensive root systems, and shrubs haven't been much affected, and certainly reflect their higher drought-tolerance.

Conditions this summer have me thinking about waterwise gardening (a 'new' alternative term for xeriscaping), as we basically don't believe that putting in irrigation systems is a sustainable option. I think the term 'xeriscaping' makes people think about desert landscaping or high elevation drought-adapted western plants, but I like the term 'waterwise gardening.' Even though I know we're hardly in the low rainfall zone at an average of 50" annually, our local cities and muncipalities are encouraging voluntary water use restrictions, and some are now mandatory in a severe drought year.

Being a waterwise gardener means choosing plants that can withstand dry spells, and flourish without lots of supplemental water. Here in the SE, we can grow lots of great plants that fit that description. Clues to drought-tolerance come from native habitat (grasslands, prairies, dry woods, etc.), plant habit (deep tap roots or fibrous storage roots), leaf color and texture (gray leaves are reflective, waxy or thick leaves are water-loss resistant).

Some of my favorite 'tough plants' from this summer have been blazing star, purple coneflower, black-eyed susans, oakleaf hydrangea, Salvia species of all sorts (including the purple Salvia leucantha shown above, Vaccinium (blueberries), Rosemary, Nepeta (catmint) hybrids, garlic chives, anise-hyssop, and certainly all the native trees. Only the relatively thin-leaved tulip poplars, maples, and dogwoods have looked really stressed, where, in contrast, the oaks and hickories are looking fine.

Lush leafy landscapes and abundant lawn grasses transpire large amounts of water and often need additional water added beyond the regular rainfall amounts.

I'm looking around and seeing what in our landscape might fall in that category. Fortunately, most of the native plants (perennials, shrubs, and trees) from this part of the U.S. are well-adapted to long periods of summer drought, and have been pretty nonplussed faced with weeks and weeks of no rain and extreme heat. The exceptions are many of our favorite plants that are native to the mountains, but not all of them. There are also some of our native understory trees that have large, thin, leaves and show water deficits quickly, too.

But, I do want to have a garden that I won't worry about if we're away in the summer and am not around to do water triage. Of course, my container plantings will be on their own, too, in that case, too!

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