Mr Millard is in despair: the new puppy is ripping up the garden. “But he has to dig, sweetie,” I remonstrate. “It’s in the DNA of a border terrier to dig.” This cuts no mustard with my spouse, who starts wielding trowels in his beloved herbaceous border with a wild look in his eye.

Because, of course, we are into the barbecue season – that moment when you start hanging little candles around outdoors and when lifestyle guides start going on about “seeing your garden as a second dining room”.

Tenants do this too, of course. Anyone looking to rent at the moment will make a beeline for anything with a barbie area at the back – and anything with a half-decent garden will get a better rent.

Weirdly, however, most tenants are utterly useless gardeners – at least, in my experience. Indeed, the posher they are, the more hopeless – or, perhaps, the more thoughtless. “We have a classic example,” says Marc von Grundherr, a director at Benham & Reeves Lettings, in central London. He refers me to a six-bedroom, £10m house in Kensington, which his company rents for a spicy £4,500 a week to people such as oil magnates and investment bankers, who jet in from New York with their giant families. The house has a grass lawn at the back. Well, occasionally it does.

BACKGROUND

• Tales of a landlady: Tax reforms

• Into the sunset

BACKGROUND

• Tales of a landlady: Degrees of success

• Tales of a landlady: It pays to shop around

• Tales of a landlady: Residents only

• The ties that bind

• How low can you go?

BACKGROUND

• Tales of a landlady: Avoiding the agents

• Tales of a landlady: In the dock

• Tales of a landlady: the age of reason

• Tales of a landlady: Heroes and villains

• Tales of a landlady: High maintenance

BACKGROUND

• Back to the ’burbs

• A waste of energy?

• Tenants like gardens, but not tending them

• In the doghouse

• Parking mad

It’s eviction time

Can investors profit from the rise in repossessions?

• It’s eviction time

BACKGROUND

• Do property workshops work?

• A letting gamble

• Spread betting

• When buy-to-let turns from a hobby into a living

Tales of a landlady: Persistent complaint

How can lettings agents justify annual renewal fees, asks Rosie Millard

BACKGROUND

• Landlords: halo or horns?

• Bidding wars

• Time to quit the ring?

“Every tenant we put in there, every single tenant, has used the garden like a football pitch,” marvels von Grundherr. “The garden is always trashed. Always. We warn them to look after the garden. They always say they will. They never do.”

One of the problems could be the football posts in the garden shed. “Yes, well, after they find the football posts and put them up, the garden is like a mud bath,” von Grundherr says in an exasperated tone. “All the flowers have been trampled on. There are no flowers there now. Eventually, we confiscated the football posts between tenancies. The next family installed a trampoline – just as bad.

“All tenants like the idea of a beautiful garden. But once they start living there, they treat the property as if they were in a hotel.”

One landlord of my acquaintance, Paul Johnson, was so fed up with his tenants’ lack of green fingers that he short-circuited the problem by employing a full-time gardener. “About 20 of our properties have gardens,” says Johnson, who has a portfolio of 40 houses and flats in Newcastle upon Tyne. “If you leave a garden, it goes to wrack and ruin. Tenants never care for it.”

Each of his gardens provides some hard space, a built-in barbecue and a few plants in tubs. Johnson estimates that employing a gardener costs him about £200 per house, per year, which he pays for. The gardener does everything: watering, cutting hedges and generally making things grow. All the gardens have an outside tap, and most of the properties are on terraced streets with rear entrances, so he doesn’t need a key. Very efficient.

Other landlords rely on a stiff clause in their tenancy agreement to make sure that everything is cared for. Brian Styring owns 17 rental properties around Coventry, 13 of which have gardens.

“It says in the agreement that they have to look after the garden, and I have threatened to withhold the deposit if they don’t,” he says sternly. “But most tenants are useless at gardening. At best, they cut the grass.”

Perhaps unsurprisingly, Styring says that long-term lets are your best bet if you are hoping for some horticultural magic. “Long-term tenants are not afraid of spending money on the garden. One of mine built walls, extended the patio – and even put in a series of water features.”

Slap on an extra cost for garden upkeep, advises Mark Shack, a lettings agent at Fraser & Co, whose catchment area is central and west London. “Every tenant wants outside space, but none of them wants to garden,” he says. “They occasionally ring us up asking for gardeners. Why they can’t just pick up a Yellow Pages, I don’t know. Or a spade.

“You have to assume that you, the landlord – or, if you are having it managed, the agent – will have to look after the garden. You can charge more for that; £60 a month seems about right.”

Won’t tenants run a mile? Apparently not, says Shack – this seems to be the season for cracking good rents, as the sales market is booming. There has been a shortage of houses for sale, so many would-be buyers are forced to stay renting, particularly in London. “Because the sales market is buoyant, there are not many rental properties around,” explains Shack, who looks after 500 of them. “Why? Because landlords are selling up. I would say that 40% of my landlords are keen to sell. Every time a tenant moves out, the property goes on sale as well as back onto the rental market. It usually gets sold before it gets let.”

Hence, the few properties still to let command strong rents – especially if they have outside space – and you can slap on extras such as £60 gardening duty with impunity.

Why are Shack’s landlords selling? Great prices and nasty interest rates. The old two-pronged approach. Never fails to get us landlords keen to offload.

buytolet@sunday-times.co.uk

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