What to do in the garden in April

What to do in the Garden in April

  April is a great time in the garden with spring in full bloom. The weather is still unpredictable; anything from a heatwave to ground frosts and sleet, and it is best to be prepared. Tender veg and bedding plants will still need to be protected by cloches and fleece. Slugs and snails are about and they view the young shoots of Delphiniums, Hostas and lettuce as the equivalent of caviar: protect the new growth- advice on how to beat the slugs.  

Buying and Caring for Bedding plants

  If you have a greenhouse or frost free area you can save money buying bedding plants in April. This means you can buy small plants which are cheaper and grown them on and take advantage of the gardening offers. Sowing from seed can be time consuming and tricky; both on the web and in garden centers there is a great choice of plug plants both for bedding and vegetables. These small plants need a frost free environment, and as much all round light as you can achieve, (greenhouse, conservatory, window sill or porch,) and care with watering, increasing watering as the plant grows. When the plug plants arrive they can be very tiny and in small thumb size pot. 

These tiny plug plants need potting on immediately,  but take care to move them just up one stage in pot size. If you put a small plug plant into a large pot it will not thrive. If you are intending eventually to plant the plugs in containers, when the plants are more established, it's a good idea to plant the container and grow on in the greenhouse until ready to plant out. This will help the plants become more mature and established in the container before placing outside and produce more flowers.

When to plant out bedding plants?

Best rule of thumb is when risk of frosts has passed, which tends to be towards the end of May. You can plant out before then but keep an eye on the weather and if frost is forecast you will need to protect with a cloche or fleece. A good tip when growing bedding plants is to nip out the growing points to produce a bushier plant otherwise some plants, particularly petunia, fuchsia, verbena will grow leggy later in the season. Advice on planting out bedding plants and the best bedding plants to grow.


Pruning in April

  Early April is a suitable time to prune Hydrangea Macrophylla, the common Hydrangea and they look generally as in images on the left, usually pink or blue, but also white. If it is an established Hydrangea prune down to a bud or pair of buds and cut out about a third or a quarter of the older, more woody growth each year to make for new growth. If the Hydrangea is newly planted just prune down to a bud until the plant is more established with plenty of growth. Hydrangea are a lovely summer flowering shrub; tips about growing different types of Hydrangea

 It's not too late to prune Buddleia davidii which helps to keep them in shape and flowering. Advise on how to grow and prune Buddleja.  April is also the time to prune Lavender, including both French L. Lavender Stoechas, and Cotton Lavender (Santonia species). Prune Rosemary and Sage and as with Lavender, avoid cutting into the woody parts of the plant. It's a good idea not to prune anything during severe weather and delay pruning if spring is very poor. April is the last chance to prune Cornus to maintain strong red colour for the winter is cut down to within a few buds to the base. Early flowering Erica (Heather) can be trimmed back once flowering has finished.

Cutting off growing point on sweet peas

Growing sweet peas 

 March and April are suitable times to sow, and in late April early May, plant out sweet peas. It is hard to beat sweet peas for colour, height and scent to a garden border. Sweet peas like moisture and are best planted in an area not to dry as that will encourage mildew. If you have time line the trench with newspaper to aid moisture retention. Sweet peas are on time consuming to grow, but very rewarding. 

Growing advise and tips about sweet peas and video on how to plant and grow sweet peas.

Generally, even thought quite hardy, Sweet peas need to be hardened off before planting outside which means acclimatising the plants to the outside conditions. Put plants outside on warm days, increasing the time spent outside until they are used to the weather and ready to plant out. Do this over a period of time so the young plants are fully ready for the rigours of the weather. It is advisable not to plant out during a chilly spell, this can knock back sweet peas (and any other young plants veg or bedding) and if conditions are poor and cool they could take weeks to pick up. If its cool they can hang around in pots longer.

If you are growing from seed or buy as small plants a good tip is to pinch out the growth point, the tip, which will make the plant shoot sideways which will prevent it getting leggy and make a bushier plant with multiple flowering stems instead of just the one. In the image the growing point is being cut off to encourage the plant to bush. With spring sown sweet peas you should do this at least once. Sweet peas can be sown into toilet roll holders which are ideal for growing all types of peas and beans to give a long root run. You will see when you come to plant them out, the roots are full down to the bottom of the tube and often curled around. The point to be careful with toilet roll holders is to take care to water directly on top and avoid soaking the tube as the cardboard will degenerate if it is too wet for too longer. Given that to get a decent crop of broad beans, runners peas and french beans means dozens of seeds, buying root trainers is expensive and the cardboard tubes work well enough.

 Seed and  Grow summer annuals  

Cobaea scandens by the Sunday Gardener the cup and saucer plant

This is another great summer annual, Cobaea scandens known as the Cup and Saucer plant. The advantage of sowing annuals is that you can buy a wide range of seed and grow plants you rarely see in the garden center. Cobaea Scandens is very tender, a native to South America and a lovely climbing plant to have as part of the summer display. The specialist seed catalogues have a fantastic range of seeds and its great fun to grow something unusual. Amaranthus caudatus common name Love lies bleeding is another exotic looking annual which is easy to grow from seed. 

Both need warmth to germinate and to grow on in frost free environment and delay planting out until they are good-sized study plants. Other good annuals which have a bold splash of colour are nasturtiums and cornflower both are easy to germinate from seed.

  Feed shrubs

As the soil warms up and everything starts growing in earnest, April is a good time to give garden shrubs a feed just as the growing season is starting. Sprinkle a general fertiliser around the base of all the shrubs and plants. Suitable fertilisers would be blood fish and bone, Growmore, Chicken Manure and slow release pellets. Handle with gloves and don't do on a windy day unless you want to sprinkle yourself with blood fish and bone. Dig in gently just under the surface and if rain is not imminent water in as well. Some shrubs such as Camellias, Rhododendron, Magnolia will benefit from specialist ericaceous feed and for Roses a specialist rose feed is best.

  Tie in new plants growth 

New growth on plants and climbers will benefit from being tied in. Over the years I have tried many types of plant ties, simple string, bendy ones, green metal ties on rolls but I favour simple raffia ties. Raffia is very strong, doesn't look too intrusive on the plant, cheap, easily available and doesn't look offensive if it blows around or ends up in the compost heap.  Raffia is also soft and forgiving as a tie and if you wonder why that is a good idea check out the tomato tie

As the flowers fade on Tulips and daffodils, dead head but leave the foliage to die back naturally and do not knot as the foliage aids feeding bulb for flowering next year. 

If you have had baskets of indoor bulbs these can be planted out after flowering for display in the garden next year- always plant 3x depth of bulb.

Why not sow a wildflower patch ? 

A wildflower patch creates a real splash of colour and you don't need lots of room and time. There is an easy way to create a wild flower patch by using a pre seeded roll or matting, which is quick, easy and foolproof. If the idea of having a wildflower patch appeals, but it always seems much too much like hard work when seen on TV/mags, try this easy way - for detailed step by step growing guide follow the link to wildflowers. Whether using a pre seeded roll or seed, the area needs to be free from weed and the soil warm enough for germination.

  Caring for Hellebores

Hellebores are starting to fade and go over during April, depending on how they look, this is time to cut down the stems. The new growth can be seen at the base of the plant and care is needed to ensure this is not snipped instead. The taller Hellebores, argutifloius - the Corsican hellebores, is prone to flop all over the place by this stage and is hard to stake. It is best chopped taking off the flower and stalks down to the ground although the other Hellebores can be left alone.

  Stake Perennials

Many Perennials will need staking support for the summer and April is the time to start staking Perennials, especially the early flowering ones, such as Peonies. If staking is left too late it can be difficult to place the stakes in place over, or around the plant, without damaging the emerging plants. I always leave it too late and find myself in May with lots of top growth which I have to try and thread through a suitable support,  and there is a real risk of damaging the plant.

Harden off plants 

Plants grown in protected conditions, newly purchased from the garden center or grown in a  frost and wind free greenhouse, do not do well if they are planted outside in the garden or veg plot without a period to "harden off", which means getting the plant acclimatised to the weather. On mild days in April, put the trays of bedding plants and tender veggies outside and bring back in at night under shelter or glass. Over a period of time gradually extend the time outside until eventually the plants are only inside /or covered, in the event of frost.

Lawns tips

April is good time to feed the lawn with High nitrogen fertilizer after scarifying , and then it is ready in March/ April is the first lawn cut, blades high to start with and lower as the spring and summer moves on. For all year round advise on maintaining a good lawn and ideas on growing a summer maze

April in the Veg plot

Start planting out potatoes

  April is the traditional month for planting out salad and early potatoes. Late April is good for second early potatoes and  for planting Maincrop, which means potatoes can be chitted throughout the month ready for planting out. Whilst it is good to get the potatoes planted, no gardening rules are hard and fast,  and as always advice is tempered by the weather. If there is a cold spell delay planting until later in the month.  Advice on how to plant and grow potatoes

Potatoes take up a lot of space in the veg plot, and if space is at a premium potatoes are easily grown in large pots. 

At this early stage in April bear in mind that the top growth on potatoes is vulnerable to frost and will need protection if frost strikes. Cover with a fleece or cloche. Also, given that April and May can be among our driest months it is important when growing potatoes not to let the tubs or containers dry out. If you are only growing a few potatoes you can plant them all out together later in April. There are many other vegetables which are suitable for growing in containers.

Which Vegetables to Sow in April

The weather can still be very cold in April and so it is important to distinguish between the hardier veg and the more tender. 

In sheltered areas in April you can plant outside the hardier vegetable such Broad beans, beetroot, carrots, Swiss chard, summer cauliflower, kohl rabi, lettuce, leeks, radish, turnip, spring peas and perpetual spinach.

The more tender vegetables need to be protected and germinated and grown on under glass, in a greenhouse or conservatory. If you are growing the more tender vegetables such as courgettes, squash, peppers, tomatoes, cucumbers, aubergines, celery, celeriac, french beans, sweetcorn and globe artichokes, they will need to be grown in frost free conditions until ready to be planted out in the veg plot from Mid May on-wards, when the risk of frost should have passed, depending on where you garden in the country. 

 One of the problems when growing from seed is that the seedlings can get leggy. To prevent this,  if germinating using a propagator, remove as soon as germinated to avoid conditions which are too warm. If germinating on a window sill, it is important to physically turn the seedling container around because when the light source on one side, i.e. a windowsill the seedlings will grow to the light which can make them leggy. By regularly turning the pot around it helps to reduce this. 

April is also a suitable time to sow in the greenhouse, for planting out later,  Peas, beans-French Green and Runners. To avoid gluts later in the season, sow at regular intervals so the plants flower and fruit at regular intervals. All peas and beans need a long root run and are best in root trainers which are quite expensive, or toilet roll holders which are cheap. Tips and advise on growing peas and beans .  

The planting order for the bean family is Broad Beans can be planted out in April they are the hardiest of the bean family, followed by Runner beans and French beans if it is sheltered or in May with frost protection.

Which vegetables to plant out in April

  If the weather conditions are right and the soil warmed up, you can sow direct into the veg plot the hardier vegetables such as carrots, broad beans, onions, garlic and purple sprouting broccoli. Carrots always need protection against carrot fly and this needs to be a physical barrier such as euro mesh, as in the image.  Carrot fly will severely damage the crop and although it is a nuisance to erect mesh around the crop, it is the best protection. Specialist varieties of Carrot such as 'Flyaway' are less vulnerable to carrot fly but not guaranteed free. Aim to sow or plant veg successively every fortnight works well. 

If you notice that the carrot seed has failed to germinate it maybe because the soil is too cold and sow again later. Carrots can be slow, and sometimes difficult to get going but trouble free once they have germinated.

If you are companion planting April is a good time to sow say, poached egg plants,  but only once the veg are in situ, as poached egg plants are great for pollination but they will not transplant.

April is a suitable time to plant out strawberries either in the veg plot or containers but remember to protect from the birds later when the fruits start. Covering the plants with a cloche will help to get an earlier crop but do not forget to water under the cloche. Strawberries are easy and fun to grow.

April is also a good time to plant onions and garlic both of which are really easy crops to grow. All that is needed is to plant to the correct depth in a sunny spot and they grow themselves. A great advantage of growing your own garlic is that the choice of varieties available on sale to grow now is really extensive. Both onions and garlic store really well so will over winter ensuring you have a plentiful supply of both for months, well into the following winter.

Video guides: how to plant onions and garlic and growing tips and planting beans of all types and advice on germinating from seed.

  How to pot up Seedlings

Some of the vegetables sown earlier, such as tomatoes, and cucumbers maybe ready for potting on. To do this select another plant pot which is just a little bigger by a few centimeters and fill with compost.Press down gently on the compost to remove air pockets which present as little vacuums for the tiny roots.  Lift the seedling out gently by its leaves, not stem, sink into the pot. If the seedling has gone leggy (long spindly stem ) sink it in deeper, fill in and water gently. It's very tempting to put into a larger pot but small seedlings will not thrive in big pots. This means,  for example when growing of tomatoes, it may be necessary to pot on 2/3/4 times to place in the eventual container or grow bag. Video advice on How to pot on tomatoes

Start growing Herbs

Herbs bought in the supermarket are expensive and don't seem to last very long. April is an ideal time to sow under glass the tender herbs, basil, coriander, dill, Thai basil, and tarragon which you can plant out later in the year or carry on growing in pots in a sunny spot. If you are sowing Parsley and struggle to get it started, keep sowing as it can be tricky to get going but easy to grow once it has germinated. Growing your own herbs is easy and allows you to grow different and interesting varieties which are hard to find in the supermarkets such as Thai basil which is just as easy to grow as regular basil and gives a great flavour to stir fries. Other hardy herbs can be planted out in pots or in the veg plot such as chives, thyme and Oregano. A word of warning about growing Oregano also know as Marjoram (Latin name Origanum) which is very aromatic and great in Greek salads, lovely, easy to grow and it tolerates most conditions except extreme wet; also very attractive to bees and insects so a great wildlife friendly plant. But, and here is the problem, it is exceptionally vigorous and will self seed all around the garden and you will need to be vigilant to pull out any new plants if you don't want an Oregano garden. More about growing herbs