When it comes to the subject of dryland gardening, I do have some thoughts and concerns. And the first thing to note is that there are a great many myths and stories on the Net about this subject. My only though on this is that you know Abraham Lincoln said that all things on the Internet had to be true to be there. (including this article) 🙂
What are the issues in dryland gardening
The first is understanding what plant selection is appropriate and then figuring out how to save/conserve water.
But before we get to plant selection, we have to understand basic plant physiology.
- As a rule of thumb, vegetables you eat are going to be around 90- 95% water. So no matter how you approach it, water conservation and applying water in appropriate ways is going to be the issue with vegetables.
- Perennial flowers require water to produce flowers and the first response of a perennial to water stress is to reduce flowering.
this means we want practical approaches
So if your objective is to beautify your surroundings, then plant choice may be your main concern with water conservation is going to be a secondary – but still critical – option.
In other words, start with the right plants first and then add water saving techniques later.
If your objective is to eat from your garden, then you’re looking at water conservation techniques with plant selection as a minor consideration.
In other words, vegetables don’t respond well to a lack of water. Many of them get diseased or die when you reduce the water so you can’t select a tomato for example that survives well in dryland conditions. You get your tomato first and then figure out the techniques that will allow you to grow it without using too much water.
In my experience, no plant is going to thrive under water stress – some will survive better than others but nothing thrives. And this is a critical difference to understand.
No plant thrives under water stress, but some survive better.
But having said that, some plants do have lower water needs than others.
The choice in vegetables is far more confusing and less is known about individual variety selection. For example, we have a tomato called, ‘Mayo’s Delight’ (yes, named after my better-half, heirloom seed expert Mayo Underwood) that was “supposed” to be a cold-season tomato but turned out to be the biggest producer under high heat and our growing conditions.
There are so many variables in soil and location that saying, *this* variety is better, is next to impossible.
Tomato ‘Mayo’s Delight’ named after my better half Mayo Underwood
My recommendation for vegetables is to start your own plants (heirlooms if you want to save your own seed) and always grow at least 2-3 different varieties of the important crops to you.
In this way, one of those varieties will always perform better and one will always lag behind. But the laggard in one year will turn out to be the best performer in another. If you find one variety is consistently poor over 3 years, drop it and try another.
In this way, you’ll discover three varieties that produce good crops for you in any given weather condition that gets tossed at you.
water conservation rules of thumb
This is going to be the most important section and the easiest to implement for most gardeners.
Organic matter in the soil acts as a giant flywheel, holding water and making it available to plants as they require it. The more organic matter in the soil, the higher the water holding capacity so your objective is to get as much organic matter into the garden as possible.
You can add organic matter by digging it in (peat moss, compost etc) or you can simply use a mulch to allow the microorganisms to do the digging for you
Mulch does several things – the primary thing being to reduce soil moisture evaporation by a huge amount. When you cover the soil you stop the sun and wind from evaporating moisture and blowing it away.
It also cools the soil by shading during the summer heat. Mind you, this cover stops the ground from warming up early in the spring as well. Think of mulch as something to even out soil temperatures – reducing the swing to either heat or cold.
Mulch also adds organic matter to the soil as it decomposes. It is the easiest way to get organic matter to the garden I know of. Lay it down and all the soil microorganisms do all the heavy lifting or heavy digging.
Use something you like the look of for ornamental gardens and something that decomposes much more quickly (such as straw) in the vegetable garden.
Three to four inches deep is the recommended depth.
Mulched vegetable garden
Simple Water Conservation Techniques
- Ditch the overhead irrigation systems for all parts of your garden. Install drip irrigation to get water to those areas that really need it.
- Get rid of automatic timers and make the decision to run those drip systems yourself.
- Buy timers that allow the water to run for one hour and then shut off.
- Consider using old-fashioned systems of applying water. For example, if you bury an unglazed flower pot in the soil (plug the bottom hole) it will slowly allow water to pass through its sides. (cover the top to eliminate evaporation) Plant crops immediately next to these pots so their roots can take advantage of the slow leaks on the pot-side.
Simple Drip System
I’ve written about using plastic jugs before. Put a very small pinhole in the bottom or bottom side of a gallon container. Bury it or set it on the ground next to your plants ( it will empty faster if on the surface) Fill up the container and put the top back on. It will slowly leak water out the pinhole to provide a slow release water source to nearby plants.
Dig a hole approximately 18-inches across with as straight sides as you can. Plant around the hole. Fill the hole with kitchen green waste such as vegetable peelings (that refuse holds a lot of water) and alternate green waste with a thin layer of soil. The water and waste will quickly be colonized by worms and roots so you’ll have an instant compost bin and small water reservoir around this hole.
Doug’s Summary Notes
- There are no great plants for serious dryland gardening in the north.
- There are “better” plants.
- Vegetable varieties are going to be a trial and error thing in different parts of the country/continent because of huge variations in temperatures, soils, and water availability.
- Water conservation is the key to dryland gardening
- Mulch is the single easiest thing to do in all gardens.