Quick tips to revive soggy lawns, by garden expert Helen Yemm

How to reinvigorate waterlogged lawns, add interest to a magnolia that rarely blooms, and stay safe on tripod ladders

Redefining a lawn edge using a half moon shaped cutter, also known as half-moon iron
Redefining a lawn using a half-moon edger  Credit: gapphotos.com

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.

This week’s Back to Basics aims to help bogged-down beginners but it may also be of use to anyone for whom the sodden winter (now hopefully behind us) provided a new kind of shock: for the first time many of us experienced severe waterlogging - or worse - in the garden.

I regard myself as one of the latter, although most of my slightly elevated garden got off relatively lightly; it was not flooded – merely wet to the point of making gardening virtually impossible except when working off paths. Only one area of shaded, heavy, compacted soil (in my front garden) became a muddy, mossy mire for weeks after being repeatedly inundated.

The general mildness – almost total lack of frost – in this part of the country (the South East) means that moss has had a winter-long field day, and is now almost totally elbowing out the grass in the soggiest areas of my front garden. In other, less watery areas, the grass is almost supernaturally green and has barely stopped growing all winter.

As soon as the ground was dry enough to mow (it only took a stiff breeze and two to three hours of sun), blessing the ultralight “wheelprint” of my battery-powered mower, I cut the unevenly vigorous grass on a high setting. This created at a stroke and, almost literally, a level playing field. I also smartened up the whole garden by using (sparingly) a half-moon edger and the long-handled upright shears to sharpen up the rather fuzzy lawn edges.

Irregular mowing restarts now, it seems. In a few weeks I will lower the blade, but never to the lowest setting, even in summer, since “scalping” a lawn only encourages moss and creeping weed invasion.

Elsewhere, I dragged at the moss with a lawn rake, drawing it all towards a central point to avoid spreading it further, before carefully gathering up and binning it (not in my domestic compost bin). I then, in an attempt to temporarily aerate the worst parts of the “lawn”, attacked the area with a garden fork (this is not a job for weaklings), driving its tines repeatedly at least 10cm into the sticky, rooty soil and wiggling them backwards and forwards before pulling out the fork. I eventually punctured the entire area where water had been most reluctant to drain. That’s all for now.

My imperfect “lawn” will be, after a fashion, eventually restored. Grass seed germinates more quickly the later you sow it, so I will wait a few weeks before casting it around.

I may feel moved in the autumn to go further and use a hollow-tine gizmo with which to remove small soil plugs from the lawn (a more efficient aeration method) and even top-dress it with a sandy loam.

Might I suggest, finally, that readers do as I did several years ago: install paths of stepping stones that will permanently improve access in the worst areas of winter bogginess.

Space them carefully, however – get the slabs in the wrong place and you will find yourself forever mincing (or alternatively loping) across the lawn.

A reluctant magnolia

Jim McLennan sent me a picture of his daughter’s young Magnolia grandiflora, planted in a small garden close to a much-pruned bay tree to hide a fence. It has only ever borne one flower (last year). Would it flower more if pruned, and if so, by how much, he asks?

Unlike its generally generous spring-flowering deciduous cousins, this is a slow-growing, rather lazy evergreen magnolia that doesn’t flower at all for at least a decade after planting. However, even mature specimens often seen tucked against the warm walls of grand houses, where they can become massive trees, only produce, during the summer, a few of their massive lemony scented blooms at any one time (inset).

Newer varieties (of which this may be one) are a little hardier and more energetic, but not much. So, no, I don’t think pruning is the answer. But it seems to be doing well, so rescuing it from the rather boring bay tree and giving it a good feed (of something suited to acid-loving plants, like rhododendrons) might be a good idea. It is hard to see from Jim’s picture, but if it were possible to do so without causing local havoc, I would dig out the bay and encourage Daughter to plant something that looks more interesting against a backdrop of the magnolia’s dramatic shiny leaves.

Tripod ladders

We have an acre of garden that involves a lot of lofty pruning, the main bugbear being a 50ft long internal laurel hedge, planted on a bank so that it is almost 2m high on one side and almost twice that on the other.

To date, my husband has used a conventional ladder and needless to say there have been a few (thankfully only pride-bruising) “episodes”. Have you any opinions on tripod ladders? Are they really stable and would one work for us, do you think?

Pat Brown – via email

A Niwaki tripod ladder Credit: Niwaki

I do have a (very strong) opinion – I have a tripod ladder and could not possibly contemplate gardening safely alone, as I always do, without it. The ladder’s admirable stability is achieved by a combination of two widely splayed legs with claw-like feet and a third leg that is easily adjustable (via a spring-loaded “peg”). The third leg can be shoved right in to the hedge you are cutting, enabling you to get really to it without compromising that stability, and there are versions that even have three adjustable feet.

There are two main importers of these super-lightweight Japanese-designed ladders, Henchman and Niwaki (mine is a Niwaki). Both have demos on YouTube and both offer a range of sizes and provide endless technical advice about optimum safe working heights - but are substantially different. I suggest you try to see them “in the flesh” - perhaps if you know someone who owns one (I bought mine at a garden show).

My one and only regret is that I did not buy the next size up. My hedges keep on growing and I seem to be getting shorter.