April in the Garden

As mentioned last month, we are coming to the end of the period in which it is practicable to be planting bare-rooted material, or digging up and moving around woody trees and shrubs. If the weather remains relatively cold and wet, into the beginning of April, it may still be possible to get away with some bare-root planting but, if you do, any plantings left this late will need more diligent care, especially watering, during the growing season as they will not have had the time to grow new roots before spring is fully sprung.
As one door closes another one opens; the lengthening days and increasing average temperatures combine to encourage herbaceous perennials to start growing with alarming speed. Hopefully you will have had a chance to mulch any perennial beds by now but, if not, it’s still possible to feed the expanding plants with a general purpose fertiliser (I still favour good old ‘fish, blood and bone’) and carefully weave a good carpet of organic mulch around the rapidly emerging leafy perennials.
It’s easier to mulch before the plants have entered into growth, when it doesn’t really matter if the mulch covers up the still dormant stools, but doing it now, more slowly and carefully, at least means that emerging weeds can be removed at the same time and plant supports, preferably pea sticks, inserted around all those perennials which are prone to collapse later on in the growing season. The appliance of your chosen fertiliser can also be more accurately targeted towards discreet clumps of perennials rather than a more general scattering.
Herbaceous perennials can be propagated easily, before they are too advanced in growth, simply by chopping sections out of the clump while they are still in the ground or by lifting the whole stool and carving it up with a sharp spade. Pot up some sections into fresh compost, creating new plants, then replant the remaining third, or so, incorporating a handful of general feed into the planting hole. Remember to water in well, to settle the roots, even if the ground is already wet.
With rising average temperatures and a diminishing risk of hard frost there’s more opportunity to sow hardy annuals this month than there was in March. Also sowing lawns from scratch can take place now, following rigorous seedbed preparation, as long as you can provide some sort of protection from heavy downpours which would otherwise wash the seed and fine tilth away.
If you have not already done so, you will certainly need to start cutting the lawn in April applying the usual common sense to avoid doing it during wet weather or if frosts are likely. Make sure whatever sort of mower you have is cutting proficiently and, where possible, set the cutting height a good notch or two higher then you would normally. Getting the lawn back under control is a real ‘feel-good’ task and sets the rest of the garden off to perfection.
Plants which have been wrapped up in fleece, to fend off the worst of the winter cold, can be unwrapped during mild spells. Keep the fleece close at hand for rapid deployment when frost threatens. Open up cold-frames, greenhouses and conservatories, whenever it is sunny, to encourage ventilation and begin the hardening off process. If you took tender perennial cuttings in the autumn, and they are still in pots or seed-trays, then these should be separated out and potted up as soon as growth resumes.
Here in the south west, especially if you are fortunate enough to live within a stone’s throw of the coast, the risk of frost is diminishing now but it’s still too early to rule it out completely. For this reason it is too early to plant out really tender bedding plants, no matter how tempting the garden centre displays may be, as they could, literally, be wiped out overnight. Having said that, because there is a danger that the choicest varieties may sell out before optimum planting conditions are with us, if you do buy them now they can be potted into larger pots, once you get them home, and kept in a frost-free place until all danger of frosts has passed.
The same goes for planting up containers and hanging baskets. You can steal a march on the season if you have room, maybe a porch or conservatory, to keep things well lit but protected until they can go outside. It’s very satisfying to plant up your summer containers with tiny plug plants, or bedding you have raised yourself from seed, so that they can establish well, and practically double in size, before they go outside next month.
If you have acquired dahlia tubers, or kept your own in frost-free conditions over winter, they will be stirring by now and will need potting up into fresh compost so that they can start to grow roots and shoots before going outside when there is zero chance of frost or really cold nights. It is possible to remove, with a sharp knife, some of the early shoots from dahlia bulbs in order to pot them up into gritty compost and propagate new plants from them. The potted up shoots will need to be placed into a lidded propagator, or enclosed in a plastic bag, and kept moist, but not wet, until they have successfully rooted in a few weeks time. Regularly check them to ensure that they have not succumbed to rotting off, removing any that have, keeping them somewhere light but not scorching.
My final thoughts are that the galloping pace of the growing plants is only matched by the speed at which pests and weeds can multiply as the season progresses. Vigilantly patrolling, in order to deal with pests before they can get out of control, is the order of the day, as is the timely removal of any weeds as soon as they emerge and become distinguishable from your ornamental plants. If you are an inexperienced gardener you will inevitably remove a few self-sown, garden worthy, plants at this stage until you begin to recognise what is a weed seedling and what is not. I like to stick to the mantra “if in doubt, weed it out” rather than end up in the position that your garden is overrun with something really pernicious (in my case; hairy bittercress)!