What to do in April
Grow some edible flowers such as heartsease, (Viola tricolour) or pot marigolds and nasturtiums, sow now and they look very pretty in soups and salads. Borage is a brilliant allotment plant as it self seeds and is really good for attracting bees as well as looking great frozen in ice cubes ready to impress your friends in the summer in a fruit punch or Pimms.
Tomatoes are growing very quickly and it is now time to pot them on, as with all plants it is best to move plants to one or two sizes larger than the pot they are currently in. This can mean having to repot them every two weeks although it is now warm enough to plant them in large pots in the greenhouse in their final positions. However, if your tomatoes are going outside it will be another month before you can put them out.
You can save yourself a lot of trouble by sowing the seeds directly into a peat or coir pot that can be planted directly into the next pot size. Tomatoes are best planted slightly deeper in the next size pot as this encourages rooting. Pinch out any side shoots as you are doing this. If you some more plants you can let the side shoots grow on to around 8cm and then use them for cuttings.
Early potatoes should be earthed up now. Main crop potato varieties can be planted now. Start them off by chitting them. Good main crop varieties include King Edward, Cara and Pink Fir Apple. They can take quite a while to produce shoots so start them off now.
It is important to sow sweetcorn early. The best idea is to sow it now if you have a green house that is frost-free, or you can sow them direct into their cropping position in May. Courgettes and squashes are easy to grow so sow now in 7cm pots – two to a pot, with the seeds on their side to prevent then rotting off. Make sure you keep them frost free.
The first batch of early sown peas can be staked and tied in if they are not clinging by their own tendrils.
Start to bring on crops of carrots and parsnip under cloches to get early crops and to spread the harvest period.
Fruit trees are now coming into blossom and they will be vulnerable to a surprise late frost so use horticultural fleece or old net curtains to protect the flowers over the next few weeks. The fleece works by trapping warm air under it and this is enough to protect the flowers. The new tiny fruitlets are just as vulnerable as the flowers so when the days are hot and sunny and the sky is clear you need to think ‘cold nights’, and cover up the blossoms and tender new shoots.
Hardy annuals such as clarkia, love-in-a-mist, poppies, and nasturtium can all be sown direct into well prepared soil in the position you want them to flower. You can also try love-in-a-mist and poached egg plants. Poached egg plants act like a landing stage for hoverflies and planting these in your vegetable beds will really help to keep down the aphids as hoverflies love eating them. Sow in drills running in different directions for a more natural look. Nasturtiums do better on poor soil so sow them in any stony inhospitable land that that you want to cover.
Now that our part of the country has officially been described as an area of drought we must pay greater care and attention to any replanting that we are carrying out for if, as now we have a hose pipe ban, watering will be rationed. Water butts are a must and it is a good idea to collect water butts of any description
As well as saving precious rain water, adding moisture retaining compost and well rotted manure to the soil when planting or dividing perennials will help. This is especially important when growing sweet peas in the flower garden or peas and beans, otherwise known as legumes, in the allotment.
It is probably a little early to talk of sitting by the pond but, on warm days this is a place of great activity for already there are frogs and toads going through their courtship rituals and you can see the bottom of the pond and any subaqueous activity that might be taking place. The oxygenating aquatic plants are bursting into growth once more and those attractive plants, that sink to the bottom of the pond in cold weather, are lifting themselves skyward again.
There is one plant that is great for the pond is Ranunculus lingua, the giant buttercup which likes to roam around on the bottom of the pond before the flowering stems burst through the water in early summer.
If you have water lilies in your pond now is a good time to divide them – they soon become congested and don’t look very good at all when this happens. Choose a warm day to do this as getting muddy when it is cold is now great fun!
Spring is a time for feeding – it’s worth just going round with a bucket or pelleted chicken manure and giving everywhere a handful and then lightly rake it in afterwards. It’s quite economical – for one big tub does for everything. There is no need to buy something special for particular plants.
Watch out for early pests, such as slugs and snails, yes them again! Especially after it has been raining – try and use organic slug pellets to deter them and make cloches out of thin gauge chicken wire and bend in into a low tunnel, threading wire through the ends to anchor it into the ground. Use more netting to seal the ends in – these can be used again and again. They won’t keep aphids off however, or caterpillars as the cabbage white butterfly can get through the gauge but it will keep off bigger pests.
Why not plant some summer flowering bulbs such as lilies and gladioli – leave these until the end of the month as you want to avoid their emerging shoots from being attacked by the frost. Gladioli look really good planted in among vegetables and you can use them for cut flowers – go for the Gladiolus murielle (previously acianthera) they are white with a chocolate throat and are very beautiful.
There are always lots of questions about what to do with Narcissi when they have finished. Don’t tie them up with elastic bands or tie them in a knot! If you do this you will deprive the leaves of light and then they won’t plump up for next year as the leaves take in sunlight and turn it into starch reserves stored in the bulb ready for next year.
I prefer to plant daffodils that are small such as Narcissus ‘February Gold’, ‘Jetfire’, ‘Jenny’ or ‘Hawera’ as these have less foliage than the large ones and then when they have finished they don’t look so messy.
If you are going to grow Dahlias now is a good time to begin to prepare the ground and plant them out – again at the end of the month as they are frost tender. Make sure you dig in plenty of organic matter as they are hungry plants and mark each planting spot with a stake so they you don’t damage the shoots when you hoe between them.
If you have a fruit area make sure that you keep it well watered and mulched at this time of the year. If you haven’t already planted strawberries then buy some pot grown plants now, it is best to grow three different types if you have the space and then you can have early, mid and late season varieties