Pots filled with good quality, premium potting mix provide ideal conditions to grow most plants. As well, pots are a wonderful way to garden in a small space. As they are portable, they can also be moved to avoid weather extremes such as heat, frost and even to shelter plants from the deluge of wet weather that’s been experienced in many areas recently.

Potted plants that are exposed to heavy rain should first be checked to ensure they are not too dry or too wet. Sometimes rain doesn’t thoroughly wet containers – especially if they are very leafy or partially sheltered from the showers – so, even during rain events, they may need additional water. Pots can also get too much water, especially in prolonged wet and rainy conditions.

Potting mix is designed to provide good drainage, but if the pot is sitting in a saucer, in a cover pot without drainage holes, or if the drainage hole or holes in the base of the pot have become blocked, then the potted environment can become wet and soggy, leading to plant dieback or death.

When the potting mix is wet, the tiny air spaces in the mix and around the roots hold water instead of oxygen, which causes root death. Wet potting mix also adversely affects beneficial microorganisms in the potting mix.

As well as leading to root rot, wet soil can be invaded by lichen and moss. The potted plant may be affected by disease such as powdery mildew. Pest activity may also increase.


Get hands-on to check your outdoor pots and ensure they're draining well post-downpour.


Inspecting your pot

As part of regular plant maintenance, and particularly during weather extremes, regularly check the potting mix using a finger to probe into the mix. This will reveal whether the potting mix is dry, moist or wet. Lift the pot – if it feels light, it is dry but if it feels very heavy, it may be waterlogged. Follow up the finger and lift tests by visually checking the base of the pot. Roots protruding from the drainage hole can block the drainage of water from the pot. The appearance of roots also suggests that the plant has outgrown its container.

Drainage holes can also be blocked with dirt or because coarse material has been placed in the base of the pot. Ants can also block drainage holes when they build nests in pots.



Improving drainage

Where the pot plant has just had too much water (the mix feels wet and the pot is heavy), but it is draining efficiently, all will be well. If more rain is forecast, move the pot to a sheltered spot so it doesn’t get any wetter.

Also assist the pot’s drainage by elevating the pot onto pot feet, a stand or bricks. As well as helping the pot to drain, elevating the pot makes it easier to regularly inspect drainage holes. Flower Power stocks an extensive range of pot stands and pot feet - shop them here.

If the pot's drainage holes are blocked, try unblocking them - for example, by poking a stick into the hole. If the drainage hole is cleared, the pot may be able to drain and all will be well.

However, if the hole can’t be unblocked, re-pot the plant into a larger container with fresh potting mix. If the pot only has one drainage hole, assess whether it is possible to make more holes in the base to improve drainage before it is used again.

If wet soil conditions have led to problems with dieback, root death or disease, or if the plant has been too wet for a long period of time, treat the plant with a fungicide such as Yates Anti-Rot. Follow up with regular treatments with a seaweed tonic such as Seasol.


Elevating outdoor pots onto stands can assist with drainage when conditions are wet.

Repotting waterlogged plants

If your plant has to be re-potted, use it as an opportunity to remove any rotted root areas. Cut away diseased or damaged roots using sharp, sterile secateurs. Also, make sure you select the best potting mix for your plant. There are potting mixes for specific types of plants that are designed to provide not only the nutrients a plant needs, but also its ideal growing conditions such as drainage or water retention.  Succulents, cactus and orchids for example are grown in coarse potting mix which provides the drainage and aeration they require. Flower Power's Supersoil range contains quality mixes for a range of specialised plant needs. Don’t try to assist drainage by adding coarse material to the bottom of the pot. While this was advised many years ago, it actually hinders the drainage of modern potting mixes.