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Watering the vegetable garden in summer: 10 basic rules
Watering is very important for the health and growth of vegetables. At our latitudes, it’s also a must. All plants need water, albeit in very different quantities, and our vegetables are among the most demanding, precisely because they have been carefully selected by mankind and have always been grown with the support of irrigation. Watering is crucial for a successful harvest. However, the biggest risk is overwatering, rather than underwatering.
Water is essential for life, including plant life. With lack of water, plant activity stops, and after an extended dry period the plant may die. Luckily, a plant with a good root system can also find the water it needs deep down, or even get it from some underground allies, such as a mycorrhizal fungi. A short-lived vegetable that is used to nutrients at root hair level will not have a sufficiently developed structure to survive in drought conditions. Therefore, it is up to us to ensure that it gets the right amount of H2O that it needs.
How? With the pollutant-free FITT Force watering hose or with a drip system.
What happens to plants when left unwatered
Plants consist of 80-85% water, which they need for all their life processes.
They need it for photosynthesis, to develop cells, to take nutrients from the soil in liquid solution, for leaf transpiration, essential for lowering the temperature in hot weather. Water also helps to keep alive all the soil organisms that process nutrients and make them assimilable by plants.
With not enough water, plants cannot develop, growth stops and they eventually die. Before this happens, plants stressed by lack of water will send out signals that can be easily interpreted, such as wilting – a method that plants use to reduce sun damage by exposing less surface area to sunlight – or early seed production, a mission that must be accomplished at all costs before they die.
There is no such thing as a perfect watering technique, not least because every garden is different. The plants will guide you if you learn to understand them.
Here are ten rules to remember for watering your vegetable garden as efficiently as possible and avoid fatal mistakes.
1. Always water in the evening or early in the morning
It is necessary for plants to have water available during daytime, when the photosynthesis process is active. Therefore, water must be available to them at sunrise. You can water early in the morning but also in the evening or the night before.
2. Avoid thermal shocks
Watering at cooler times avoids thermal shocks due to the temperature difference between the water and the plant tissue. To avoid this problem, cold water from, for example, a well, can be channelled into a container, where it can warm up to ambient temperature. Of course, the water must not be too hot either, or our greens might get cooked!
3. Use non-chlorinated water
The best water is rainwater.
Spring water and fresh surface water, such as from lakes or rivers, are also great. The water we extract from the earth through wells is, on the other hand, still immature, meaning that it has not yet completed its natural cycle and should not be disturbed. But where available, this is nevertheless one of the most used in the vegetable garden. The least recommended water of all is the water from drinking water networks, as it is treated with chlorine to avoid contamination. Chlorine is not good for plants, and even less for the micro-organisms living in the soil. Again, storing it in a tank can be useful, to allow the chlorine to evaporate before use.
When watering, water the soil and not the plant
Top irrigation replicates the most natural way for plants to receive water. However, watering the green parts of the plant can lead to problems, especially the development of fungal diseases.
Therefore, top irrigation should be avoided in the evening, as it will create a humid environment for many hours, and therefore favourable conditions for fungal growth. On the other hand, watering the leaves during hot weather can lead to scorching, due to the magnifying glass effect of the water droplets on the leaves. If the water is only supplied to the soil, the roots can do their work without such drawbacks. A completely wet soil, such as from rain is, however, on the whole much more vital.
4. Don’t overwater and reduce waste
Water is precious and should not be wasted.
Moreover, watering more than necessary is not good: too much water clogs the pores of the soil and does not allow the roots to breathe, whereas oxygen is essential for the activities and the survival of the plant. The use of drip irrigation systems is a very effective way of reducing waste. It allows the water to reach where it is needed and distributes it gradually, so that the plants have time to assimilate it before it’s lost. But if used correctly, even watering hoses can help to only use the necessary amount of water. The correct use of adjustable spray guns, such as the one that comes with FITT Force, ensures that water gets to where it is needed without any waste. In addition, if the water jet is not too strong, compacting and the formation of the soil crust can be reduced.
5. Pay attention to water quality
It is important to know the characteristics of the water that we use, analysing it to measure the presence of pollutants. Unfortunately, the uncontrolled and pointless use of pesticides, chemical fertilisers, herbicides and the likes, is increasingly polluting both surface and deep waters. Therefore, even if unintentionally, watering can pollute the soil. It is at least possible to avoid harmful substances that can be controlled, by selecting watering equipment made of suitable materials.
6. Choose the right watering hose
Watering hoses should be selected very carefully, to avoid those that release harmful substances, such as phthalates and lead. FITT Force, the strong and compact heavy-duty garden hose with fittings and multi-jet spray gun or continuous spray nozzle is suitable for watering large ornamental and vegetable gardens, as well as for every day and domestic use. FITT Force is free of PVC, lead, phthalates or other harmful chemicals.
7. Know your plants’ needs
Different species have different needs, even among cultivars. In addition, plants need more or less water depending on their current stage of development. Lastly, controlling the amount of water can also affect the quality of the produce we are growing. The learning curve is virtually endless, which makes horticulture extremely stimulating.
Generally speaking, younger plants need more water because they have smaller roots to search for it, while at the end of the cycle it is better to give less water, to improve the sugar content and the flavour of the fruit to be harvested. Searching among seed keepers, it is possible to find plants selected for good drought resistance.
8. Take the weather and the soil into account
It is important to remember that plants should not be watered if rainfall is sufficient.
It is also important to pay attention to the wind, which dries out the soil more quickly. When the weather is very hot, plants need more water to continue growing. Like us, they need to ‘sweat’ to lower the temperature of the tissues exposed to the sun, which is why they require more water during hot weather.
To understand what to do, it is helpful to get used to observing the soil, digging a few centimetres deep to see if it is damp. A dry soil down to 5 or 6 centimetres from the surface can be tolerated, but below that, humidity is required for the survival of the plant. Different types of soil will react differently to watering. Clay soils retain water for longer and help it to spread horizontally, whereas sandy soils drain more quickly and the water tends to penetrate downwards. This must be taken into account during watering.
9. Reduce evaporation
Mulching can help reduce evaporation. Mulching means covering the soil with a layer of artificial or natural product to protect it from thermal stress.
Mulching offers many other advantages and natural locally sourced mulches should be selected. Natural mulches (e.g. straw, hay, leaves) also offer the advantage of replenishing the soil with organic matter. They also retain water better and better allow it to penetrate the soil.
10. Help the plants to fend for themselves
Ensuring a sufficient amount of water for our plants is easier when their root system is well developed.
There are many way we can help resistance to water stress.
Care should be taken during planting, to avoid compacting the soil below plant root level, about 30 cm from the surface, as this may prevent the roots from going lower and could also cause waterlogging of the roots. A soft, humus-rich soil will not only promote root development, but will also retain more moisture for longer. Many plants can create with their roots symbiotic associations with fungi, to help them to reach distant sources of water and nutrients, in exchange for the sugars created by photosynthesis. These underground unions are called mycorrhizae, from the Greek mykos, fungus, and rhiza, root. These associations are more common in soils not worked by mankind, while they are more difficult in case of vegetables only intended to live in the soil for a few months. However, during sowing and transplanting it is possible to enrich the soil of our vegetable gardens with fungi spores, with which the young plants will be able to establish positive symbioses.