Irrigation in the vegetable garden
Due to the current climate scenarios with increasingly hot and drier summer seasons, water represents a resource of primary importance even within a vegetable garden, large or small, a treasure to be preserved with efficient irrigation and, if possible, with a collection and reuse system.
But how can we best water our horticultural plants and when should we intervene to avoid drying out?
We start from the soil, making sure to place a layer of mulch on the surface to try to reduce water losses through evapotranspiration, thus retaining humidity in the event of low rainfall.
We can transplant the seedlings outdoors at the most suitable time in relation to their life cycle, generally in spring or autumn, and try to assist them in the first stages of growth to guarantee correct root development, thus obtaining healthy and strong plants that will be able to produce abundantly, in detail:
let’s try to let the first centimeters of soil dry out slightly between one irrigation and the next without however letting the plant dry out and at the same time avoiding waterlogging, an factor predisposing to root rot;
if possible, the best thing is to water early in the morning or in the late afternoon when it is cooler to lose less humidity through evaporation, trying to apply the water directly to the surface near the roots rather than on the foliage to avoid possible burns caused by the sun’s rays as well as the spread of fungal diseases.
During the growth phase we do not exceed the quantities and frequencies but we water with regular doses also in relation to the type of crop, i.e. a marrow plant will have different water needs compared to a carrot or cauliflower, following the general rule in maintaining constant soil humidity, avoiding stagnation.
Further care consists in dosing the water supply in relation to the weather trend, i.e. in sultry and droughty heat we can intervene with larger doses compared to a rainy and cool day.
To define the frequency of watering, we try to monitor the plants in our garden, intervening before signs of significant water stress appear such as leaf drying and curling, brown edges of the leaf blades and stunted growth.
We can use a hygrometer to detect the moisture content of the soil, thus understanding precisely the moment in which to intervene, finally we reuse the rainwater by positioning containers also near the rain pipes of the roofs or we place one or multiple collection tanks to be possibly connected to an irrigation pump.
What type of water to use?
To water our vegetable garden we can use rain water, often considered the best, alternatively water from aqueduct or canal, paying attention to the pH value that must not modify the level defined as optimal for our crop, specific for each species; to control this parameter we can use a pH meter or more simply “litmus papers”.
Irrigation methods
When we are about to create a vegetable garden, it is of primary importance to plan in advance the way in which we intend to supply water, that is, we can opt for manual irrigation and/or using an automatic irrigation system; in the first case we can be more precise in relation to the actual needs of the plant but we will be more constrained, in the second case with a correct setting of the frequencies relating to the quantities supplied we will be able to save water and time.
Which system to use?
On sale we find different types of irrigation systems for vegetable gardens, including drip or micro-irrigation, a network of pipes distributed in the cultivated area with drippers or simple holes strategically positioned near the base of each plant, known for its high efficiency through precise, slow-release delivery that ensure the right amount of water to each plant without waste, also preventing fungal diseases compared to a sprinkling system.
To create an automatic drip system, it is advisable to purchase good quality pipes, perforated or not, as well as a control unit with rain sensors, a pressure regulator to avoid possible damage to the drippers, taps to connect to the pipes, T-connections and elbows.
Another technique we suggest is subirrigation, already used by the ancient Egyptians using terracotta amphorae, a naturally porous material capable of gradually releasing water, placed near the root systems in the soil; this system is still applicable, alternatively, starting from knowing the texture of our soil. We can create a system, automatic or not, by ploughing at variable depths in relation to the cultivated species of self-compensating drip lines which will allow the leakage, using special drippers, of the water that will reach the roots directly by infiltration and capillarity, thus keeping the soil moist and reducing evaporation losses as well as guaranteeing a balanced relationship between air and water reducing compaction of the soil.
Whether we choose to water manually or with a system, let’s remember that our plants need water in adequate quantities for their vegetative development and subsequent flowering and fruiting since they themselves are made up of water on average at 90% and because the so-called blue gold plays a fundamental role in their vital functions such as respiration and photosynthesis.