In this weekend’s garden column, I discuss how important watering is for your plants. This includes summer bedding, roses, shrubs, trees, perennials, annuals and lawns.
As we head into summer, we tend to have days without significant rainfall. As I discussed in a previous column in regards to lawn care, we can see reminisce of last summer’s drought on our lawns.
Did you know us humans would only survive 48hrs without consuming a liquid? Crazy!
Well plants are similar and water is vastly important to a plants growth and longevity.
The plants use xylem and phloem to pass nutrients and much more back forth from the leaves to the roots. These are very similar to our arteries and veins and work in a similar principle.
This exercise of passing these nutrients and water from the very bottom, the roots to the new growth on the very top of trees, flowers and shrubs is by a capillary force.
This allows the mightiest of trees to rush nutrients and water all the way up to the new growth. This action is basically where there is a pull on one and not the other.
Almost all water contains properties of different nutrients such as calcium, iron and magnesium. These are all vastly important for plants growth.
Slight defiance can lead to discolouration of the veins, leaves and stunted growth. An example is bottom end rot in tomatoes which is caused by inconsistent watering and imbalance of calcium being made available.
This is the uptake of Carbon Dioxide C02 and the release of Oxygen 02. Stomata which are small pores in the leaves uptake air and through a chemical reaction release it as oxygen.
As you can imagine during this process water vapour is also lost. Once the plant realises that there isn’t sufficient water available it will shut down these stomata to keep water stores available.
Once this occurs, the plants growth is slowed as they cannot carry out photosynthesis.
Diseases & Pests
Once plants become stressed cause them to become vulnerable and susceptible to diseases and pests. Once their systems shut down, the plant can’t defend itself properly from attacks.
Similar to when us human’s immune system becomes weakened we tend to find it hard to battle other sicknesses.
As you can imagine during these warm dry spells of weather, the temperature can rise significantly. Generally speaking, most plants will significantly slow down their growth rate at around 28 degrees Celsius.
This is to ensure they retain as much water moisture as best as possible. So watering helps cool them down and reduces further stressing occurring.
This is when the plant has reached peak saturation and there is still water available to it. This can be even more detrimental to them then under watering.
As the saying goes, it’s near on impossible to put toothpaste back into the tub once it has been removed. This can apply in this situation as well, it’s very difficult to remove excess water from your soil or compost once it has been applied. Most plants generally don’t like their roots sitting in damp, cold water conditions.
There’s a point of no return which is called ‘The Permanent Wilting Point’. This a point of no return as all the moisture has been used up by the plant and has no other sources to avail of. Carefully monitoring of your plant is critical. Look out for leaves or new growth wilting. That will be the first signs of under watering.
When to Water?
Little and often is the key to watering. I believe in watering early in the morning. This helps prepare your plant for the day ahead.
Watering late in the evening means your plant will sit in damp conditions for many hours. This may result in an increase in pest and diseases as well as affecting your plants growth.
If you have any questions on this article or any other gardening questions please feel free to contact me. Contact details are below.
BAgrSc, Horticulture, Landscape, & Sportsturf Management
Facebook: Conor Gallinagh – Horticulture Consultant