Monthly Advice - April Jobs in the Garden
APRIL IN YOUR GARDEN
- Our cold store is now crammed with bareroot hedging for planting over the next four weeks. As long as you can water them, any hedge plants will do well planted now and this is now probably the best time of all to plant beech hedging.
- However do not cut back newly planted native hedging now (do it in November if you forgot). However if you have not coppiced your shrubby dogwoods such as Midwinter Fire and Westonbirt, then you must do so this month if you want a show of coloured bark next winter.
- Although April is usually one of the best months to plant a conifer or evergreen (think holly or box) hedge, it is too late this year because evergreens are in full growth after the warm winter. Deciduous hedging is fine because we keep it dormant in our cold store.
- The wonders of modern technology really apply here. Our fruit trees are now in cold storage where they will sit happily for another couple of weeks. We keep them like this because today most commercial orchards are planted later than they used to be (some in May or even June). The trees respond fantastically well to the warm soil and longer daylight hours. All that is required is to keep them well watered and to make sure that after they flower any fruitlets are removed so they can build their strength for next season. Our guarantee still applies, of course, so keep planting. Anyone who thinks they have missed the bare root season need not despair!
- Any shoots that have been damaged by frost can be cut back to a healthy bud lower down the shoot, or to a stem junction.
- For ornamental trees, the bare root season is over, but as with fruit trees April is one of the best months for planting pot grown trees. An hour or two before you plant, water the plant in its pot. Then ease out the rootball before following the instructions on the website as to how best to plant a tree. Make sure you have a generous sized hole, and that when you have finished the top of the compost is level with the ground around it.
- Cotinus coggyria (smoke bush) and the copper elder, Sambucus are well known for their colourful foliage. The brightest and best foliage is to be found on new stems. So for the most impact, prune a full grown specimen hard now to encourage new foliage or if the plant still needs to fill its allotted space, leave some of the shoots unpruned to allow the plant to grow larger without compromising on colourful foliage. As always, once you have pruned any plant it is worth applying a general fertiliser and watering well to help it to recover.
- The lovely Japanese quince and shocking yellow forsythia flowers will nearly be over. When you can, cut the flowered side shoots back to 2 to 3 buds so that they flower well next year. If you are training a quince or forsythia against a wall, then tie in as many shoots as you need to fill in gaps and then prune all the flowered shoots to one or two buds from their growing point.
- Unless you are an organic gardener you will need to use a fungicide to spray against black spot on your rose plants. This is a job that will probably need to be continued throughout the summer because it is difficult to control especially after a warm winter. There are of course roses that are resistant to black spot and it is worth investigating these. The golden Graham Thomas, the pale pink rambler Francois Juranville or the shocking pink Rosa mundi are all blackspot resistant.
- Keep an eye out for aphids - they will be bad this year. Brush them off or, for the non-squeamish, squish them where you spot them. There are also sprays you can use against aphids but always spray in the evening when fewer pollinators like bees or butterflies are about.
- Your climbing roses should be tied in horizontally to cover any walls or eyesores and to encourage flowers. Any uprights can be bent over (gently) to force more flowers along the stem, otherwise they just tend to flower at the top leaving a long gap.
- If you think just how floriferous a rose can be it is becomes pretty obvious why they do need a bit extra. Use something like Vitax Organic Rose Food to help them along. Order enough to repeat the dose in June.
- April is the time for that balancing act of feeding blackcurrants, blackberries and hybrid berries with a high nitrogen feed to encourage the enormous amount of growth they will put on over the season but not feeding them so much that you end up with lots of sappy, soft growth that is too temptingly delicious for pests and is susceptible to disease….message is, follow the instructions on the fertiliser packet.
- Weed and then mulch around raspberry canes and other soft fruit plants to suppress any competitive weeds that will take all the nutrients and water from the soil to the detriment of your fruit crop. You have to hand weed round raspberries as they are too shallow rooted to hoe.
- Plant a few annuals like Phacelia close to, or even in, your fruit cage to attract friendly predators like hoverflies that will then eat any pests that might otherwise have attacked your fruit. Keep a vigilant eye on your fruit bushes for larvae, aphids and such like to try to nip any infestations in the bud. And again, if you must spray, do so in the evening.
- If your blackcurrant flowers emerge red, as opposed to a pinkish grey, then your blackcurrant might have been infested with a mite that spreads a virus throughout the plant. Should this occur, dig the bush up, burn it and start again with a mite resistant cultivar of black currant like ‘Ben Hope’ which we will be selling next season.
- Rhubarb forcers should be in for a treat in April because it is time to remove the forcing pots and feast on the pale stems therein. Best practice once you have harvested your forced stems is to then leave the plant exposed to the elements but feed it well and resist the temptation to pick any stems that grow subsequently.
- Unless you are growing a mildew resistant variety of Gooseberry like Invicta, check for signs of mildew on your gooseberries and if needs be buy a fungicide specifically for it. Good pruning, feeding and watering should also help to prevent mildew in the future.
- Grape vines can put on as much as 3 m of growth in the season so keep on top of those rapidly expanding shoots and tie in those that you wish to keep in place, thin where necessary and stop any shoots that are growing too long so that you encourage grapes not foliage.
- April sees your clematis beginning to really grow away. Give them a helping hand by tying in the first shoots and from there on in they should clamber quite happily. If they begin to encroach on other plants you may need to divert them back to a cane or official support.
- This is lavender ordering time. Deliveries begin when the weather is right – sometimes as early as the middle of April, but more usually in May. Order early to beat the delivery rush and to get the best lavender plants. If you want a hedge or edge, and if you want a real show of flowers this summer then you need 2 year old stock that has been grown in 1.5 litre pots. They are always in short supply so order early to avoid disappointment. "Plugs" will die on you (unless you are very lucky) and 9cm plants will take an age to get going.
- Really good time to give your lavender a light trim to keep them bushy and compact (especially if you forgot last autumn…). Take 2-4 cm off shoot tips and any remove any spent flowers. Without doing this your plant will end up with an increasingly sparse and woody centre. Try to avoid cutting into old wood – more than a year old – because there are no guarantees that your lavender will regenerate foliage and flowers from old wood...
- Dead head early spring flowering bulbs such as daffodils by snapping off the head behind the swollen part so that the plant does not waste energy by forming seeds. You can leave the stem intact and then allow it and the foliage to die back slowly concentrating any goodness left in the plant back into the bulb ready for more flowers next year.
- Recent research suggests that leaving the foliage for 6 weeks is long enough for this process and you can then mow the rather untidy leaves away. Growing daffodils amongst large leaved plants like hostas will disguise the demise of the leaves and looks much better….if you can keep the slugs from the hosta leaves.
- Plant out summer flowering bulbs like dahlias and gladioli into the garden so that you have plenty of flower arranging opportunities over the summer. If you have clay soil then put the bulbs on a layer of grit sprinkled on the bottom of the planting hole.
Olive and Bay
- It is easy to think that just because the weather is not too hot that plants in pots do not need watering. Mark in your diary to feed olive trees with phostrogen once a month and check regularly to see that the soil in the pots has not dried out.
- If you have failed to administer a dose of slow release fertiliser to any potted bay trees that guard your doors, April is as good a time as any for this annual necessity to keep your bay tree in fine fettle.
Other Stuff - including soils, lawns, ponds, terraces
- Some of my favourite plants are those like Verbena bonariensis, Aquilegias (Columbines), Digitalis (Foxglove) and Pulmonarias (Lungwort) which self-sow everywhere for free so that your garden is filled with flowers at very little cost to your time or purse. You can move any of these seedlings and re-plant them now or, if this slightly random approach is not your idea of fun, then weed them out before they take hold.
- Don't fall behind with your weeding. A quick hoe now will save hours of weeding later in the year.
- Slugs and snails love the warmth and wet of April so begin night time patrols around the garden to remove them - or deploy slug pellets. Counterintuitively, less is more with slug pellets so do not scatter them like hundreds and thousands around precious plants but space them apart and re-apply after rain. Nematodes that you water into the soil are also effective against slugs. Or for the fully organic, then jars filled with beer, cider or watered down syrup dug into the ground, leaving the lip of the jar proud of the surface, should catch lots.
- The vegetable garden should be getting into full swing, even if it is not that productive yet. Harvest purple sprouting broccoli and the last of any leeks or kale. Stock up on labels, canes, netting, composts and seed trays and sharpen your pencils in readiness! Night time temperature and soil temperature are two indicators as to when you should start to sow vegetables outside. If it is still cold at night, hold off, however warm the day.
- Bear in mind that clay soils take much longer to warm up than lighter, sandy soils, so it is worth delaying your seed sowing if you are gardening on heavy clay. Your plants will catch up if sown later but seeds are more likely to rot or just not germinate in cold, claggy soil. Another indicator is to watch out for weeds. If they are proliferating, then the chances are your vegetables or annuals will have a sporting chance of germinating too.
- Once you have decided it is safe to sow, April should be the busiest month for succession sowing lettuces, beetroot, chard, and some pretty annuals for your pots and borders like marigolds, poppies and the unusual blue green cerinthe. Wait until the end of the month to start vegetables like squash, courgette and French beans off. Ideally sow these inside in an unheated greenhouse to give them a good start before they have to go out and do battle with the elements and the slugs.
- Traditionally potatoes were planted on Good Friday. For our money you are safer to wait until April but even then be prepared to fleece the ground if a frost is forecast.
- By April there are no two ways about it but you have to be mowing your lawn once a week. Start on a high setting at the beginning and over about 6 weeks progressively lower the blades on your mower so you cut the grass more closely. If there are weeds like docks, dandelions, plantain or thistle coming up try to dig each one out individually before it grows too enormous. Check for lumps and bumps in your lawn and try to even them out so that the mower does not scalp the grass in parts and leave tufty bits in others. Where there is any coarser, vigorous grass daring to emerge, take an old knife and cut in diagonal strokes through it, criss cross fashion, and pull out any tufts. With your mowing regime in place this should stop them establishing themselves in your lawn.
- Just as your garden looks so much better once the lawn is mown, so your lawn looks that much better if you go round with edging shears to define the edge of the lawn and the beginning of a border or hard landscaping.
- It is time to attend to any pots that are planted up with perennials or shrubs. Scrape off as much of the top layers of compost as you can without damaging the root structure. Replace the compost with fresh compost along with a dash of slow release fertiliser and maybe some water retaining gels to cut down on your watering over the summer.