Well-Watered Crops Result in a beautiful Harvest
Watering correctly is essential to growing vegetables successfully. If this is essential for plants grown in the ground, it is even more critical for plants grown in pots. In soil, the plant’s root system can grow in many directions in order to reach water. In a confined space like a pot, such is not the case. Therefore, the gardener must be more careful with the potted plants need for water.
When container gardening, it is necessary to take into account a very specific phenomenon. It is only at the beginning of growth period that we can rely on the rain to provide water to the root system. After a few weeks, the leaves begin to cover the surface of the pot and the rainwater trickles down the leaves rather than reaching the soil. You need to remain vigilant, as the roots cannot reach open areas where water could seep in.
On the other hand, excess water can also be a problem. If the water cannot drain off, the roots quickly suffocate.
In addition to considering the plant’s specific needs, watering must take into account these three factors:
- – confined roots;
- – little contribution from rainwater and;
- – the risk of root suffocating.
In addition, if the pots are high-up, the phenomenon of evapotranspiration (evaporation of soil water + transpiration of plants) is increased, particularly because of the wind.
The Right Watering, at the Right Place and at the Right Moment
Whatever the situation, watering must always meet this ideal:
« introduce adequate amounts of water for the plants to the soil, while avoiding wetting the foliage ».
This approach has three goals: to provide enough water for the plants, neither too much nor too little; minimize water losses due to evaporation at the time of watering (especially high in hot conditions and reduce the presence of diseases on the leaves etc.).
The best time to water the plants is in the morning, between 4am and 10am. This prevents loses by evaporation, reduces the risk of disease (the foliage of plants has time to dry) and takes advantage of the dew. Not always available at this time? Then water between 8 pm and 11 pm (it is particularly important not to water the foliage).
Watering can be done in three ways:
- With a watering can. This method is useful only when a few pots need to be watered;
- Using a hose equipped with a nozzle;
- Installing a watering system connected to a timer. Such a system avoids the chore of watering. It is especially useful for people who are busy or need to be away often.
However, it is still necessary to check watering regularly and if need be, make “adjustments” either with a hand-held watering can or a hose equipped with a spray gun.
When using a drip irrigation system, it is important to adapt the type of dripper (3.7 liters / hour, 7.4 liters / hour, etc.) to the dimensions of the pot.
Bertrand Dumont, horticulturist, author and speaker