Burnett: Importance of proper drainage

Due to the hot dry spell we enjoyed this summer, it seems the issues normally associated with growing a nice lawn have been exacerbated.

I have been inundated this summer and fall with questions regarding turf problems both from home owners and maintenance people.

Due to the hot dry spell we experienced and enjoyed this summer, it seems the issues normally associated with growing a nice lawn have been exacerbated.

There are a few key things I look for when diagnosing turf problems and it depends on the symptoms displayed as to where I look first.

About 90 per cent of the time I am asked why the lawn is browning out or dying in patches or large areas. The other 10 per cent are questions regarding weeds, mushrooms, moss and variations of colour and texture.

Today I want to talk about the installation and the importance of proper drainage.

The B.C. Landscape Nursery Association has defined guidelines for soil composition and depths and if anyone wants a copy, email me at don@thegardenexpert.com. But here is a short version.

A properly installed lawn is one that has at least 10 cm of a sandy loam with about five per cent organic content. It is important the compacted subsoil is scarified and not left in a smooth condition after the initial excavation which causes a “perched water table.

It doesn’t matter how decent the top soil is, if the sub-soil is compacted there is no drainage and it is lack of drainage which causes so many problems with turf such as thatch build up.

Contrary to most thinking thatch is not an accumulation of dead grass clippings, it is an accumulation of dead roots that have come to the surface for air and then died due to lack of moisture. To test for proper drainage a percolation test is conducted by digging a small hole 30 centimetres wide and 30 centimetres deep, fill it with water and let it drain out completely. “Charging” the soil like this will give a more accurate reading than performing this test in dry soil. The next day fill the hole again and fix a ruler in such a way as to be able to measure the level of the water and gauge it as it drains out.

The ideal rate would be five cm per hour but anything between 2.5 cm and 7.5 cm is acceptable. If the rate is less than this a lack of air in the soil will encourage thatch buildup and several disease issues.

If the rate is faster it is difficult to keep moisture in the top soil causing the turf to become easily parched.

Sometimes browning out is associated with a simple deficiency of water due to a malfunctioning sprinkler system.

Test for even distribution of water by placing saucers or pie plates in strategic areas and comparing the rate of fill over a 10 minute time period. You might be surprised at the results.

I will continue next week with more on lawn issues including insect, weed and cultural practices.

Just Posted

Kelowna golf course ready and open for spring business

Two Eagles Golf Course opened Saturday, more to come

Kelowna-Lake Country MLA hopes annual climb will promote peace

MLA Norm Letnick’s 5th Annual Spring Climb for Health & World Peace is April 6

Possible assault to bus driver in Kelowna

A minor bus crash was reported just after 8 p.m. Friday night

Car crash nearly sends car over embankment in West Kelowna

RCMP search for driver of alleged stolen vehicle that caused crash

Update: Highway 3 reopened following rockslide near Keremeos

The slide occurred Friday March 22, at about 8 p.m. between Red Bridge and Standing Rock

Sparks fly as SUV speeds down wrong side of Highway 1 trying to flee RCMP

Captured on video, the vehicle headed westbound against oncoming traffic before crashing

Okanagan woman launches sewing studio

“I know there’s a lot of people up and down the valley that would love to sew.”

1,300 cruise ship passengers rescued by helicopter amid storm off Norway’s coast

Rescue teams with helicopters and boats were sent to evacuate the cruise ship under extremely difficult circumstances

Letter: Stop raising the minimum wage

To the editor: The government is looking for ways to put more… Continue reading

Letter: Immigration will not help other countries, or our own

To the editor: Firearms are not the culprit in all those massive… Continue reading

Letter: Sprawl destroying natural landscape

To the editor: I agree with the assessment by Ian Pooley in… Continue reading

Former Okanagan teen found safe after disappearing from YVR airport

Ethan Burnett, 14, was found safe in Kelowna on March 22

B.C. university to offer first graduate program on mindfulness in Canada

University of the Fraser Valley says the mostly-online program focuses on self-care and well being

Province announces $18.6 million for B.C. Search and Rescue

The funding, spread over three years, to pay for operations, equipment, and training

Most Read