Guide to watering your garden

One of the most frequent questions asked by our customers is ‘ How often should I water my plants?’  There is no one answer that fits all as it depends on the plant type, it’s requirements and the soil/growing media conditions. 

Watering correctly is the key to growing healthy plants.  We all know that water has become a precious resource here in the UK and are aware of the need to protect the environment including river levels for wildlife as we see the effects of climate change.  

When to water your plants: 

Watering is best carried out in the mornings if possible, but it can also be done in the evenings when conditions are cooler.  It is not advisable to water during the heat of the day as this will lead to evaporation from the soil surface.  

How much water should I give my plants: 

Watering requirements depend on a number of things - as an example, plants in containers or hanging baskets in hot and sunny weather may need watering twice a day.   

Other factors to consider are the species, size and the stage of growth of the plant.  (Plants also require a wide range of nutrients to grow well and you can read our Plant Feeding Guide here.)  

Soil type also plays a part in determining when to water, for instance, clay soils are able to hold more water than sandy soils.  Clay soils can sometimes still feel damp even if plants begin to wilt and sandy soil may feel dry even though there might still be water available to the plants roots.  

Plants in pots or anywhere their roots are restricted will require watering more frequently than those in borders where their roots are free to grow to areas where they can find water.  It is worth noting too that plants that are pot bound will also dry out quicker.  (A pot bound plant will have more roots than compost in the pot.)  

The rate that plants use water also depends on the weather.  Generally plants require more water during warm summer months than they do in cooler winter periods.  Water more frequently during prolonged dry spells or if it has been windy, which will also dry out plants.  Light showers usually are not enough as the water just evaporates or only reaches the surface of the soil.   

Plants require water at the tips of their roots - a dry surface of soil or compost may not necessarily mean that the plant needs water, therefore it is best to push your finger down to knuckle depth instead of just checking the surface.  

Indicators that the plants need more frequent watering also include leaves angling downwards or beginning to curl, less growth of foliage or production of flowers or fruit or dull looking leaves or stems.  Wilting can also occur, but this can also be an indication of over watering.  (It is important not to over water as plants do not need to be wet all of the time.) 

It is advisable to damp down greenhouses regularly to raise the humidity during hot weather by wetting the floor, overhead watering or misting.  To prevent fungal problems that can be caused by high humidity open vents and doors to improve ventilation.

How to water your plants: 

Plants require water through their roots via the surrounding soil or compost that they are growing in and not the leaves as wet foliage may encourage fungal problems.  

It is best to water thoroughly to enable it to penetrate down deeply to the root tips and advisable to do so before any drought sets in so that soil moisture levels are kept even.  Plant roots do need air as well though, so it is just as important that the soil is not too wet.  

If drought does set into a border any plants that are suffering should be given a single thorough watering either early in the morning or during the evening. 

If drainage is poor, watering may not be effective - either improve the drainage or select plants that are suitable for the conditions.  

How much water should be applied: 

This depends on the individual plants requirements (for example, succulent plants require less water than summer bedding plants), how actively it is growing, the type of soil or growing media and weather conditions.   If the soil is sandy or chalk it will require watering more frequently than heaving clay soils, however less water can be applied and any excess will drain away.  Water heavy, clay soils less frequently using a heavier application as they will hold more water.  

Containers should be watered slowly - if water drains out of the bottom a saucer can be placed under the pot to catch the water, allowing it to be re-absorbed.  Small containers can be lifted to see if they feel heavy and more water added if necessary.  

Watering methods: 

Rainwater is the first choice as tap water can contain more minerals than some plants need, especially ericaceous types such as Camellias.  Water butts can be purchased in various sizes and designs from our Watering department. 

At Poplar Nurseries we also stock a huge range of hose pipes and attachments, sprinklers, seep hoses, automated irrigation systems, water butts and of course, watering cans to make the job of watering your garden as easy as possible.  Click here to visit our Watering pages.   

Minimising water use: 

In our changing climate the RHS (Royal Horticultural Society) recommend designing our gardens to minimise water use.  Choosing the right plants for the right places is important - if plants are positioned where they are happy to grow such as ferns that enjoy shady areas or Mediterranean plants in full sun, they will thrive.  An inspiring example this is the late Beth Chatto’s Garden in Elmstead.  The Chatto family built their new home in 1960 on wasteland that had been part of the Chatto Fruit Farm when Beth’s husband Andrew retired.  Low annual rainfall was one of the challenges they faced, but this did not deter them from transforming the landscape into a series of magnificient gardens that are now a shining example of how to work with nature.  These stunning gardens include a spectacular gravel garden that is famously never irrigated and a newly designed reservoir garden.  You can also enjoy walking through the woodland, water and scree gardens for ideas and inspiration.  Beth Chatto’s was awarded the OBE in the Queen’s Birthday honours in 2002.  She passed away aged 94 in 2018 and a memorial was held at the Garden Museum in London.  Click here to view the Beth Chatto’s Plants website.  

Improving soil with organic matter will reduce moisture loss. Add this when planting and in late autumn to late winter apply as a layer of mulch at least 5cm (2in) thick to the soil surface.  You can use well-rotted garden compost, manure or chipped bark to do this and it will reduce water loss from the soil as well as provide frost protection, suppress weeds and improve plants growth by adding nutrients.  Non organic material such as gravel, grit and slate chippings can be used in dry/Mediterranean style gardens to cover the soil surface.  

Where possible plant new plants between autumn and spring.  This will allow them to grow roots into the ground before dry weather begins.  If you do plant in dry weather, bear in mind that the plants will require extra water while they establish.  

Finally, when visiting our Watering department you will find a vast array of options.  If you require assistance, please do ask a member of our trained staff who will be happy to give help and advice.