Garden writer Marc Rosenberg, who has been gardening for 30 years and has contributed to the STIHL blog since 2018, shares what he’s sowing and growing in May with a diary from his small suburban garden. Giving beans and tomatoes a head start while encouraging summer favourites to bloom early are at the top of the agenda for May. Read on to find out more!
1. Give Canna Plants A Head Start
Cannas are one of the most majestic summer flowers to grace containers and garden borders. Started from rhizomes under cover earlier in spring, plants are now growing at a rate of knots so it’s time to move them to bigger plant pots that will result in a growth spurt and earlier blooms. Plants should be watered prior to repotting and, once the pot has been eased away, roots teased out if they’re spiralling, before being transplanted into larger plant pots.
Cannas thrive in multipurpose compost although they need regular watering. As they’re tender, canna plants can’t go into their final growing positions outdoors until all risk of frost is over, so they’ll remain in a conservatory or a frost-free greenhouse for now, before being hardened off later in May. Summer bedding plants such as geraniums will also thank you for being potted on into bigger pots a month or so before planting out.
2. Growing Tomatoes In Pots Versus Growing Bags
I have a love-hate relationship with growing bags for tomatoes. On the plus side they’re the height of convenience, formulated with the right blend of nutrients that hungry crops require – simply cut out the planting hole and away you grow.
My biggest bugbear, however, is shallow compost. Even thick bags offer limited depth for root development while skinny bags can dry out quickly when temperatures soar. If compost becomes parched between watering, tomatoes can be susceptible to common problems such as blossom end rot.
In recent years, I’ve banished single-use, plastic-clad growing bags in favour of deep pots that can be re-used. Tomato plants thrive in multipurpose or John Innes No. 3 compost, with the added bonus that plant pots can be stood in saucers of water in high season, to provide a reservoir of water that stops roots from drying out. Plants need liquid feeding with tomato food regularly – under glass, start feeding when the first truss of tomatoes has set (outdoor crops should be fed once the second truss contains small, green fruits).
3. Remove broad-leaved weeds
Last month I focused on the dire state of my lawn, which was infested with moss and blighted by sparse growth. A high nitrogen spring lawn feed reinvigorated the turf and banished moss but ugly broad-leaved weeds are now rearing their heads.
Invaders such as plantain, dandelion, thistles, daisies, speedwell and clover can easily be spot-treated using a selective weedkiller that zaps the weed without harming surrounding grass. For maximum effectiveness, it’s best to spray on a warm, dry day when weeds are actively growing.
4. Sow runner beans now
One of the reasons I love runner beans is that they look just as ornamental growing up a wigwam in flower borders as they do on vegetable plots or allotments. Beans flower in red, white or even bi-colours and, if picked young, pods will be succulent and tender (leave beans to mature and they become tough and stringy).
Runner beans can be direct-sown in garden soil in June or started off in plant pots indoors in May. I always opt for the latter; not just because it gives plants a head start which means earlier crops, but because slugs and snails make a beeline for the young shoots of direct-sown beans, often devouring the lot!
Choosing a runner bean variety that will thrive in the UK’s unpredictable climate is vital. Runner bean ‘Stardust’ features beautiful white flowers and sets tender pods whatever the weather, while ‘Enorma’ is the go-to choice for competitive gardeners, as its huge pods can reach 50cm long! ‘Firestorm’ is a brilliant modern scarlet-flowering runner yielding stringless pods even in poor summers, while dwarf ‘Hestia’ with its bi-colour flowers is ideal for patio pots.
The big, speckled seeds of runner beans are easy to handle. Sow individually into pots of seed and cutting compost, pressing seeds 5cm deep. Placed in the warmth of a propagator, seeds will spring into life within a week – you’ll need to provide a stick for support until beans can be safely planted out in June.
5. Restore wooden garden furniture
Feeling the warmth of spring sunshine in the garden is always a mood-lifter, especially this season after the long winter in lockdown. Now that Covid restrictions are being eased and we can finally welcome friends and family into our gardens again, it’s time to get the garden furniture out and look forward to the first barbecue of the year.
In my garden, azalea buds are bursting into flower and lilac is at its prime but the spectacle is being let down by the sorry-looking, weathered state of my outdoor furniture. There’s no need to replace tired timber, however, as a bit of effort can restore wooden garden furniture to its former glory. Here’s how I tackled the job over the course of a weekend:
1. If garden furniture is covered in dirt and mildew, blast the muck away using a pressure washer, then leave garden chairs and tables in the sunlight to thoroughly dry.
2. Use light or medium grade sandpaper to remove previous wood stains and paints, rubbing lightly along the direction of the grain. This creates a lot of dust so wear a face mask to avoid inhaling the particles – we are all used to masks by now
3. Pay attention to slats in garden chairs, as failure to remove old paint will create dark patches when new stain is applied, leading to an uneven finish. Wipe the dust from surfaces using a clean, dry cloth.
4. Working outdoors on a day when rain isn’t forecast (or in a garage or conservatory if conditions are damp) apply teak oil or furniture woodstain using a brush, working along the grain of the timber and taking care to avoid drips, which can spoil the finish. Most treatments require two or three coats – make sure to leave the required time between each coat so the stain or oil can dry.
5. Once several coats have been applied and have dried – yes, there’s always a bit that you have missed and have to touch-up – your garden furniture will look as good as it did on the day it left the showroom, while being protected against the weather.
What other jobs are you doing in your garden in May? Do you enjoy gardening in spring? What garden furniture have you restored recently? Let us know in the comments below.