May 2019
I do apologise for being rather late with this May update – but I have been away in America on the first trip of the ‘Monty Don’s American Gardens’ series that will be shown early next year. We filmed in Washington, Virginia, South Carolina, Miami, & Louisiana. It was fascinating, very eventful (missed flights, wrong airports, blazing restaurants and broken down vans – all part of the rich tapestry of filming) and hard work and now it is a joy to be back in my own garden at this, the loveliest time of the whole year.
The whole garden – the whole of nature – is shot through with a green energy that is unstoppable and by the end of the month spills out into the fulsomeness of summer. But it is the process, the daily, almost hourly, changes that thrill me. Colours emerge at every turn – blazing reds and oranges in the Jewel garden, pinks and blues in the Cottage Garden, soft yellows on the mounds and every shade of white and green in the Writing garden. But green always wins. Every imaginable shade of green rises to glory with an intensity and freshness that no other month can match.
Time grows too. The days in this part of the world are becoming deliciously long – with dawn glowing on the eastern horizon before 5 am and by the end of the month we can garden outside until 10pm. But as I get older and another May comes around I am increasingly aware of how precious this time is. The days tumble by too fast and I have to stop and drink it all deep so I can store this May-time richness and draw upon it later.
Wildlife: newts
Last May I discovered the first newts in our pond. I was skimming off the algae dragging a net carefully through the first few inches of the water and depositing the wet green vegetation on a stone at the edge so that any creepy crawlies could return to the water before I tidied up. Then I noticed something something halfway between a lizard and tadpole – a kind of tiny alligator – walk down into the water, followed by a couple more.
These were the Common or Smooth newt, Lissotriton vulgaris. It is brown with a wavy crest along its back that is crown in the breeding season to increase its seductiveness. They develop their front legs first and then back ones (which is the opposite to tadpoles) and a favoured food of many fish. Once they are fully formed they leave the water and live in damp places on land.
Newts are carnivorous and will eat whatever they can catch – usually tadpoles, worms, shrimps and insects in the water and worms and slugs when they move to dry land.
The Great Crested Newt, Triturus cristatus,is the largest you will see in Britain and can be up to 16 cm long. It has warty skin and although, despite the name, the female never has a crest, the male grows two crests in spring, one on its back and another on its tale. Like toads they excrete a poison from the warts on their skin so tend not be eaten. They spend winter hibernating on land before moving to water in the breeding season. The Great Crested Newt is highly protected and it is against the law to damage or destroy any of its habitats or to deliberately capture or harm them in any way.
Newts need a lot of prey to sustain them as well as sufficient ponds and rivers and their numbers declined rapidly in the latter part of the twentieth century. However numbers are building back up and they are often very common locally, although still not widespread.
What to do in the garden this month:
The incredible growth and changes in May means that it is hard to keep up with the garden – go away for a few days and it can run away from you. On the one hand this is all part of the joy of the season – nature is rampant and we should celebrate that . However keep on top of weeding if at all possible. Hoe vegetables and hand weed borders and if you have not done so yet then it is not too late to mulch.
By the middle of the month tender annuals such as tithonias, zinnias, cosmos and sunflowers can be safely planted out in all southern parts and the tender vegetables such as squashes, sweetcorn, beans and
Sow French Beans
If your soil has warmed up – and only feeling it with your skin will determine that – then you can safely sow a batch of French beans, both dwarf and climbing. These are tender plants that will be knocked right back by a touch of frost and will survive but not grow if the temperature drop below about 10 degrees and then become fair game for slugs and snails. But by the time they have germinated we will be clear of those cold temperatures in most areas and the young plants can grow strongly.
Sow dwarf beans in rows in well manured soil a with each bean spaced 6 inches apart and the rows 12-18 inches apart. For climbing beans sow two seeds at the base of each support and removed the weaker of the two once one is established and growing strongly. Water them well and keep them watered throughout the growing season.
Divide and move grasses
Unlike herbaceous perrenials, grasses are best divided once they have started to grow vigorously. Lift the clump and divide into fairly substantial sections – they grow slowly so do not cut them up into too small pieces. Replant them at the same level they were in before and water in well. Keep watering them weekly until they are growing strongly.
Some grasses seed themselves freely and form crowded clumps and these can be thinned and moved by lifting entire young plants and repositioning with more space around them.
Laying turf
The beginning of May is a good time to lay turf as the ground is warm and the grass is beginning to grow vigorously so will establish quickly.
A lawn is only as good as the soil it grows on. Rather than hiding imperfections, turf tends to accentuate them whilst making it much harder to fix, so get it right before the turf goes down. Dig over the area, breaking up any compaction and removing all and visible weeds. Rotovate it well and then rake it thoroughly so that the surface is smooth and level.
Then tread over every inch, keeping the weight on your heels. This will expose any dips and hollows which should be filled and then the soil raked completely smooth again.
Then, using planks to stand on, lay the turf in courses, butting the edges tightly together making sure that the joints do not line up. Only cut when you have to and keep any shorter sections away from the edges so that they will dry out more easily than longer sections. When you are happy that it is done, water it well. Do not tread on it at all until the grass is visibly growing – which will be around 10 days.
Deadhead Tulips
If you have tulips growing in borders, deadhead them once they are past their best. This will stop the development of seed so that all the energy goes into forming new bulbs for next year’s flowers. The best way to deadhead them is simply to snap off the spent flower with the growing seed pod using your fingers.
Do not cut back the stem or any of the foliage as this will all contribute to the growing bulbs as they slowly die back.
Tomatoes
It is time to plant out tomatoes if you have not already done so, burying them deeply – right up to the bottom leaf as the buried section of stem will develop extra roots.
As the young plants grow they form shoots between the leaves and the stem and these are known as side-shoots. They grow with extra vigour and although they do bear trusses of fruit, they take energy from the plant and reduce the overall harvest as well as making a cordon plant straggly. So they should be removed as they appear.
The best way to do this is in the morning when the plant is turgid, simply breaking them off with finger and thumb. However in the evening they will be limper and may tear the plant so should be cut off with a knife.
Planting tender annuals
By the middle of May tender annuals like sunflowers, Zinnias, Cosmos or Tobacco plants can be planted out into all but the coldest gardens, especially if you have hardened them off for at least a week. Hardening off is important and will means much faster growing and longer-lasting flowers – so if you buy any of these annuals from a garden centre over the coming weeks, do not plant them out immediately but put them in a sheltered place for a week to acclimatise to your garden, as they will probably have been kept sheltered for best retail display
I like to use tender annuals both in containers and borders and in the latter I do not use them as bedding but to enrich the general tapestry of the overall planting. So I place them in groups so they make drifts and clumps rather than straight lines.
Space them about 12 – 18 inches apart in a sunny situation that is sheltered from strong winds and water them in well. As long as the temperature does not drop below 5 degrees they should grow strongly and flower well into autumn.
The Chelsea Chop
‘The Chelsea Chop’ is a piece of horticultural jargon for a prune of late-flowering perennials that is best done in the second half of May (around the time of the Chelsea Flower Show – hence the name). The reason for doing this is to delay flowering and to encourage bushier, stronger and more floriferous plants later in summer.
Plants such as heleniums, sedums, lysimachia or solidago (Golden Rod) are particularly responsive to this. If you have several clumps of these plants then cut one of them about half way up the existing growth. If you have just one big clump then reduce just one third of the plant in this way. The result will be that the pruned section will produce side shoots bearing extra flowers which will bloom a few weeks later than the uncut growth and extend the display into autumn.
Prune early flowering Clematis
The best time to prune early-flowering clematis such as c. montana, armandii, alpina and macropetala, is immediately after they finish flowering. Obviously the timing of this will vary considerably in different parts of the country but the principal remains constant and for many of us this occurs at the end of May.
Next year’s flowers are formed on all the new growth made from this period until late summer so if you prune them much later than mid to late June you will be removing potential flowers that would bloom next spring.
Pruning of these clematis is solely to maintain their size and spread for your convenience rather than for any horticultural benefit. So cut back freely, not worrying about individual stems or the position of the cut. Then when you have finished, weed round the plant, water it well and mulch generously with garden compost or bark chippings.
Sow biennials
Now is the time to sow wallflowers, honesty, foxgloves, forget-me-nots or sweet rocket for a lovely display next spring and summer. Biennials differ from annuals, which grow, flower and set seed all in one growing season, in that they grow fast from seed and develop strong roots and foliage in one season and then flower in the next.
For most this means that they germinate and grow without flowering in summer and autumn, remaining dormant over winter, then have another burst of growth before flowering in Spring and early summer.
The great advantage of biennials in our borders over annuals is that they are hardy enough to withstand a cold winter and quickly produce flowers in spring without having to wait for the plant to grow first.
Sow the seed thinly in a seed tray, cover them with vermiculite and put to one side to germinate. They do not need heat but a sheltered spot or porch will help. When the seedlings are large enough to handle prick them out into pots or plugs and grow them on so the young plants are ready to plant out in early autumn where you want them to flower next May.