After four years living in the deep south of Spain and trying to grow things, I can now dwell on my experiences.
Firstly, for me it turns out to be rather frustrating, battling the extremely high temperatures in summer and then the few nights where we actually have a few hours of frost, which will kill the tender plants. It killed our potato stalks once.
Then there is the sandy soil, where any moisture is sapped away immediately. Added to which our back garden has 15 cm sandy soil underlain with building rubble, you could not pick a worse place for a garden.
Despite that, I am growing more or less successful courgettes, peppers, tomatoes, lettuce, Swiss chard and onions, garlic and herbs. In fact, the rosemary and lavender bushes love it here so much that I have to cut them back twice a year or they would develop into a forest.
These are Mediterranean plants, so this is their home and they thrive; which cannot be said for things like chives, French beans or any other cool-loving plants.
Rucola or rocket, roquette grows in the winter months nicely. Even beetroot, leeks, kohlrabi and other cabbage do well. The main growing season is between October and May, after that comes the time of the tomatoes, peppers, sweet corn, melons etc.
As it only rains here twice, usually in November and March or thereabouts, watering the plants most of the year is a necessity.
Nigel did even install a roll-out lawn twice in the front of the house and kept it going over the summer, but it takes a lot of water and time to keep it alive. There is a native type of grass, grama, which can withstand the heat but dies back in winter, and he does not like the look of it. It originates from North and South America, genus Bouteloua oligostachya, is much coarser and spreads in stolons on the surface.
Roll-out lawn when it was put down in March
After one summer.
After two years of struggling along with stunted plants in our back garden we started the out garden or container garden. Any type of big containers, like a square 1000 liter cube or second hand palm tree pots are ideal to grow plants in, as they can be filled with good, humus-rich soil and will keep moisture available for the plants and are easier to tend too, being high off the ground.
We now have 9 big containers, where I grew this year potatoes, tomatoes, fennel, aubergines, sweet corn, leeks and carrots.
This is one solution to the bad soil and lack of rain. I have also tried out a few different forms of irrigation systems on my garden:
- water hose, surface irrigation,
3. ‘Cuban Method’
4. trench planting,
5. piped, drip irrigation,
and most essential: mulching.
- Water Hose
The traditional way of using a water hose has the advantage of flooding a plot and can be done willy-nilly, any time of day. The disadvantage of course is it takes a lot of water, splashes from the soil can infect plants with diseases and evaporation is high, if the ground is not mulched.
A pottery friend in Germany mentioned ‘ollas’ to me, which is the Spanish word for pots, in this case terracotta pots which are buried in the soil beside the plant. Ollas can be very fancy, come in different shapes and sizes. I however just stuck two cheap clay pots from the Chinese shop with silicone together, plugged one hole and dug these in. They work. They act as a reservoir for water, which seeps out really slowly over time. Here however, thanks to the very thirsty sandy soil, it is gone within a few hours, unless the soil around it is also kept damp.
The combination of ollas and water hose works well, but a lot of ollas are needed.
- 3. ‘Cuban Method’
On YouTube I found this old Cuban fellow extolling the virtue of watering only once a week thanks to his plastic bottle system. Instead of clay ollas he reuses plastic bottles, makes a small hole in the side and digs them in beside the plant to be watered.
I like the idea of reusing plastic bottles, everybody has them available anyway. So all new bushes and trees now get a two or 5 liter bottle beside them. I have placed a bamboo stick with a cork at the end into the bottle and so I can see how far the water level has gone down.
It works very well. Since my cucumbers have now a bottle beside them, they thrive as well as the cucumbers in the paint container.
- 4. trench planting
Another method is to dig a biggish hole, fill the bottom with gravel, and stick a pipe beside the plant root that will be receiving the water. Thus the water goes straight to the roots, where it is needed.
This is a good idea in soils that go rock hard and will not take surface water, again a problem we have.
- 5. piped, drip irrigation
I watched YouTube videos, I saw the neighbours doing it, I heard it from others too and it is done on a huge scale in the tunnels and green houses, drip irrigation. Over thousands of hectares of strawberries are grown this way here in Huelva province.
Advantages of drip irrigation
- It saves around 30-70 % of water.
- There is a reduction in the cost of labor.
- Suitable to use in hilly terrains.
- It also decreases the weed problem.
- There will be an increase in plant growth, vigour, and yield.
- Facilitates easy intercultural operations.
- Ease the fertilizer application
- Fewer incidences of various diseases spreading through the soil are minimized.
- It is most suitable for light soils.
- Utilization of low-quality water like hard water or salt water without contamination of the whole farm.
It is a bit complicated to get all the bits and pieces together, that’s why I shied away from it for a long time until all this daily watering and getting entangled in hose pipes got to me.
So I made a plan, got the various items in the local supplier, including a programmable watering clock.
Unfortunately the connection coming from the wall tap just is not right and water already gets out from there before going down the various pipes, which we luckily had available here on the finca anyway.
So I am lacking the pressure to have a circular system to drip irrigate all the beds.
It’s not a big area, but I wanted all beds to receive a lot of piping which is just not feasible, so back to the drawing board.
I know others also have their problems with blocked pipes or holes and some areas not receiving enough water. So the jury is out on that one.
But what I urge everybody to do, who lives anywhere at all, is mulching. Deep straw mulch is best. Here we have a ready supply from the goat sheds down the road, so my mulch comes with added nutrients.
Mulching is the very best method to:
- prevent evaporation
- prevent weeds from coming up
- preventing soil erosion
- keep the soil surface cool
- adding to humus content and organic matter
- help water absorption
- reduces the intensity of rain/irrigation water
- helps prevent soil borne diseases
- establish beneficial fungi, bacteria and worms to break down the organic matter
- protecting tender plants
- adding nutrients.
You could also use wood chips, bark mulch or dead weed matter, just try not to introduce weed seeds or roots or disease. I have my doubts about paper, because of the ink and very high carbon content.
Currently I use a combination of all the methods listed above. The drip irrigation is stalled at the moment. So watering still takes me an hour, half an hour in the back garden, which is under shading and another half an hour in the container garden and various plants all around the house.
We were lucky enough during our three week holiday to have a conscientious friend looking after our house, plants and creatures, feeding and watering daily.
And yet, still plants wither and die from the sheer intensity of the heat and are under heat stress, they cannot suck up water as quickly as it is lost.
The highest and lowest soil temperatures occur at the soil surface, and become more stable the deeper you go. What I thought is interesting is that in order to properly earth an electric installation you have to go as deep as 1.5 m with your earthing rod according to our electrician. It is at this depth the soil becomes damp, even though on the surface you think it is completely dried out and dead, devoid of all soil life, but deeper down it is teaming with soil life.
When the air temperature reaches 35 degrees Celsius, the soil temperature can go even higher than that if you have a sandy type soil. Our soils here are sand and loam and behave like concrete, making it difficult for roots of newly planted plants to penetrate and search for moisture.
Therefore any new planting is done in the autumn, when there is less heat and the hope of some rain. The vulnerable plants can take their time to drill down roots and get settled before the blazing heat of the summer.