Five 'common' garden plants which could 'devalue' your home

Giant Hogweed has the ability to grow very fast
-Credit: (Image: (Image: Getty))

Frequently gardens are teeming with an array of plants, shrubs and trees each of which can veil the presence of a damaging other. Surveyor experts have offered to help by identifying five of the most "common" garden plants that could diminish property value if left.

1. Japanese knotweed.

A notoriously intrusive weed recognised by its bamboo-like shoots and shovel-shaped leaves is Japanese knotweed. Its growth can reach up to three metres tall during spring and summer and spread 20 metres underground.

Stokemont warns of how this unyielding weed can cause considerable damage to pipework, drains, and compromise the strength of building foundations and paving, possibly resulting in foundational collapse and reduced flood defences.

Due to these potential consequences, Japanese knotweed is classified as a defect by RICS Homebuyer Reports, potentially causing a reduction in property price by as much as 15 percent, reports the Express.

The necessity to stringently inspect for this plant and promptly remove it, cannot be understated according to Bradley McKenzie of Stokemont who advised, "It is really important to clearly check and take immediate and thorough eradication actions before it gets too late."

He further urged homeowners to seek professional assistance to ensure complete removal, stressing, "We would highly recommend you seek professional help when removing them as they re-establish easily from even the smallest remains."

However, he did acknowledge those preferring a DIY approach suggesting, "If you prefer doing it yourself, pesticide would be the most effective method to kill those zombie-like plants."

2. Ivy.

Primarily seen enveloping landscapes across Europe, English Ivy's harmless appearance masks a real threat to properties by its ability to cling onto walls.

Stokemont explained that this intrusive plant is known for its ability to infiltrate cracks in walls, deteriorating the quality of mortar and introducing dampness or leaks into properties.

Bradley noted: "Unlike Giant Hogweed, English Ivy could be removed with bare hands by peeling them carefully off the wall. It is also possible to kill them by cutting their roots off and letting them dry out."

"However, not all wall-climbing plants are harmful, such as Boston Ivy, so we recommend consulting a professional before mistakenly cutting some beautiful and safe plants from your wall."

3. Giant Hogweed.

Giant Hogweed shares similar characteristics with Japanese knotweed, notably an incredible rate of growth. This plant tends to pop up during June and July, recognisable through its thick green stems bearing purple spots and beautiful white flowers in an umbrella pattern at the top.

The experts stated: "Widespread across the UK, especially around rivers and ponds, its sap is phototoxic and can cause severe skin burns or scars under sunlights."

"Though not causing direct harm to the property, buyers may still refuse to pay a higher price if present because of its high cost of removal - up to £15,000!"

4. Poplar, Willow and Oak Trees.

Majority of trees pose no harm, however certain exceedingly large ones like willow and oak can prove hazardous if planted too close to residences. This is primarily because of their extensive root systems which are capable of spreading to 40 metres, absorbing up to 1,000 litres of water and nutrients from the soil.

Pulling from their expertise, the surveyors stated: "They could live around 50 years and are harder to remove when their roots grow thicker and bigger as time progresses. Their age, soil type, location, depth all matter when deciding whether your tree is a problem. If grown too close to your property, they could lead to further risks of cracks in foundations, subsidence and other structural defects, potentially costing you £5,000 to £25,000 to repair."

5. Himalayan Balsam.

Introducing yet another weed, they pointed out that the Himalayan Balsam is originally from the Himalayas itself, having made its way to the UK in 1839.

Displaying staggering growth, the plant can shoot up to two to three metres with distinctive pink flowers appearing during the summer and autumn months.

Don't be swayed by it's attractive colours though. This invasive nuisance has an extensive geographical reach, capable of spreading 800 seeds even through rivers, potentially obliterating other plants and leading to significantly reduced biodiversity due to hoarding light, nutrients and water.

Finally, Bradley inferred: "It does not have physical danger to humans but its significant ecological impact on nature and associated laws are not favoured by buyers. So it is recommended to keep this plant controlled or eradicated, and make sure it does not spread to your neighbours' home as it can be illegal."