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How to bring dead grass back to life and revive your garden

Rake out moss and thatch to revive the lawn
Rake out moss and thatch to revive the lawn Credit: age fotostock / Alamy

Every week, Telegraph gardening expert Helen Yemm gives tips and advice on all your gardening problems whether at home or on the allotment. If you have a question, see below for how to contact her.

 

Bring the lawn back to life

My once-stripy greensward has, following near-desert conditions, the surface texture and colour of a loofah. Only deep-rooted weeds and coarse grasses have managed to survive. Will the turf really be restored once our customary Devon monsoon arrives? Or must I scrape the surface 
 off and returf it?

Loris Goring – via email

This touch of reader hyperbole brightened up the August dog days in my inbox no end. Severe though the effects of this worryingly long drought have been, I can assure you that your grass will have merely gone into deep dormancy.

Grass roots are extraordinarily resilient, and lawns almost always come back from “the dead” eventually, the roots having survived on a combination of regular heavy dewfall and the one or two downpours that I believe most of the droughted counties have had during the weeks that extremely high daytime temperatures prevailed. Recovery may be slow and very possibly patchy, and lawns will, once they have greened up somewhat and are well on the mend, benefit from more than a little TLC in the early autumn to get them back up to scratch.

This will involve raking out the remains of the “loofah” thatch, aerating it by spiking with a fork (once the ground is no longer rock hard), particularly any compacted areas, over-seeding the whole lawn (Johnson’s has developed a special fast-germinating lawn-thickening grass seed mix: see johnsonslawnseed.com) and top dressing the whole lawn with a sand/organic matter mix.

Any or all of these treatments will help to restore the lawn and toughen it up for next year, and many of them can be carried out by a local lawn maintenance franchise.

If, when you read this, your lawn is still loofah-like, it might keep your mind off thoughts of scraping and re-turfing if you were to get out there and spot-weedkill the still-green deep-rooted weeds while they are much in evidence.

A rhodo revival 

We have a nine-year-old, much-loved rhododendron on our south-facing boundary, which is now suffering because of the proximity of our neighbour’s five-year-old, now 8ft tall (despite polite requests to keep at 5ft) conifer hedge. This summer the rhododendron looks as though it is in terminal decline despite all my efforts to water (via tubes bored into the ground) and mulch it. What now?

AD – via email

Helen Yemm feeds a rhododendron after moving it Credit: Martin Pope for the Telegraph

Intransigent neighbours, the thirsty roots of conifer hedges on boundaries and the shade they cast are age-old problems about which not much can be done. But you could move the rhododendron away from the boundary slightly in order to save it. A few feet make all the difference in terms of light and moisture in the soil, and the generally improved conditions might eventually cause a growth spurt for the rhododendron.

Moving a nine-year-old rhododendron should not be terribly difficult. You will find it has a compact root system, the extent of which you can investigate now by digging around it with a spade, in preparation for an autumn move after an overnight hose-drip into its roots. Plant it with lots of added goodies such as leafmould or ericaceous compost, and water, feed and mulch it for a year or so after the disruption – doubtless you are a bit of a dab hand at that bit. It is a shame that your neighbours hedge will probably react to all your shenanigans a few feet away by growing even faster.

Flea beetle on alyssum 

Flea beetles have attacked my 
alyssum this year and I would like 
to consider an alternative white-flowering annual to replace it next year. Do you have any suggestions?

Charles Hawker – via email

Sweet alyssum (Lobularia maritima) is, along with radishes, salad rocket and wallflowers, a member of the brassica family, so is fair game for hordes of tiny black flea beetles. These have back legs that enable them rapidly to hop out of harm’s way (hence the name) when disturbed.

The beetles nibble tiny holes in leaves, spoiling a plant’s looks while generally not killing it. However, I think a good replacement would be 
 a white-flowered slumpy and spreading annual bacopa, commonly available with other “basket” annuals in early summer. It flowers all summer, needs no deadheading, just “tidying up” every few weeks, and has proved to be quite winter-hardy.

For your enlightenment – flea beetles come to a sticky end if you pass a liberally glue-smeared piece of cardboard over the plants on which they are grazing. The shade cast makes them jump upwards en masse.

This article was originally published in August 2018