Pre-soaking your terracotta pots? 'Don't waste the water', say garden experts

You may have seen this hack online or heard about it from another gardener, but should you really pre-soak terracotta pots before planting your container plants in them? The argument goes like this: if you don't pre-soak them, then your terracotta pots will absorb the water and there won't be enough for you plants at the important re-potting stage. 

Is this really true? We've asked professional gardeners and landscape designers whether your container gardening ideas will really suffer if you don't use this method. Their response may surprise you. 

Should you pre-soak terracotta pots before planting?

In a word, no – it's really not worth the effort for your patio gardening ideas. Mindy McIntosh-Shetter, also known as the 'Outlander Botanist', from Charleston, said: 'In a nutshell, soaking your terracotta pot before planting really does nothing.' If you really are worried about your plants drying out, and are 'only planting non-edibles then you can paint the inside of the pot. The paint will fill in the pores [in the terracotta] and prevent evaporation.'

Tina Huffman, horticulturalist and landscape designer at greenhousestudio.co, seconds this view: 'I would say don't waste the water. Just water your plants thoroughly once you've potted them to the point of runoff out the drainage hole and they will be fine.'

Clive Harris, the creator of DIY Garden, is even more vocal: 'Over the years I’ve potted up, re-potted and watered hundreds of plants and not once have I soaked a terracotta pot. Soaking terracotta pots is a waste of time because any moisture they might absorb evaporates within a day, less time than it takes for the plant to use up its leafy water resources.'

Why you shouldn't pre-soak your terracotta pots: the science

This may be a shock to gardeners who regularly soak their pots to prevent their plants from drying out, but it may well even have the opposite of the desired effect. Rick VanVranken, Department Head at Rutgers New Jersey Agricultural Experiment Station, explains that a pre-soaked terracotta pot will not slow down the passing of water through soil – in fact, a dry one will. Despite what often gets said about terracotta 'leaching' water out of soil, that cannot happen unless the soil is overwatered, that is 'until that soil reaches 100 percent saturation. Hence, a dry terracotta pot should actually slow the drying of the soil contained within until that soil is overwatered.'

Basically, if you are watering normally and not overwatering your plants, terracotta pots will not dry them out – quite the opposite. Rick has another important tip for gardeners working with terracotta: 'For the same reason, there is no need to place shards or other larger particles in the bottom of the pot to increase drainage because they will actually slow drainage as that layer also has to be saturated before it will drain. The only reason for the shards is to reduce the loss of soil/mix through the drain hole in the pot.'

What should you do instead of pre-soaking your pots?

Watering plants regularly, no matter what they're planted in, is by far the most reliable way of keeping them alive and thriving. Marylee Pangman, Element3 Health gardening expert and author, gives her top tip: 'People who live in dry climates (or drier than the Pacific Northwest!) can use a heavy-duty lawn and leaf bag with a drainage hole cut into the bottom and line the pot with the bag. This will retain moisture and still allow the excess water to drain. This will also prevent calcium buildup on the outside of the pot in homes with hard water.'

Terracotta is still one of the garden planter ideas gardeners like best – it's natural, durable, and it can be updated in many ways by painting. Just remember to water!