What to do in the Garden in April

 If you have a greenhouse, lean to or frost free area, you can save money by buying small bedding plants in April, which are cheaper, and grow them on in the sheltered frost free conditions. 

Sowing from seed can be time-consuming and tricky. At this time of year, there is a great choice of plug plants for bedding and vegetables. These small plants need a frost free environment, and as much all-around light as you can achieve (greenhouse, conservatory, window sill or porch.) Take care with watering, too much at the early stages, and the small plants can rot. It is best to increase watering slowly as the plant grows.

When the plug plants arrive, they are often in small thumb-sized pots, and they need potting on immediately, but take care to pot them up just one stage in pot size. If you put a small plug plant into a large pot, it will not thrive.

Later, when the plants have matured, if you are going to put them in containers or hanging baskets (as opposed to borders) it's a good idea to plant them in the container and grow on in the greenhouse until ready to plant out. This will help the plants establish a good root system in the container before placing them outside.

When growing bedding plants, 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.

Crocus has a great selection of spring and summer bedding plants.

    Early April is a suitable time to prune Hydrangea Macrophylla, the common Hydrangea, and the image left may help you identify H. Macrophylla. It flower usually pink or blue, but also white. If it is an established Hydrangea, prune down to a bud or a pair of buds and cut out about a third or a quarter of the older, more woody growth each year to make way for new growth. If the Hydrangea is newly planted, just prune it down to a bud until the plant is more established with plenty of growth. Hydrangea is  a lovely shade tolerant, 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, or rather trim,  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. April is the last chance to prune Cornus.  By pruning hard in March /April, Cornus will have a strong red colour next winter. This is a hard prune, cut down to within a few buds to the base. I have a step-by-step video guide on how to prune Cornus.

Early flowering Erica (Heather) can be trimmed back once flowering has finished.

March and April are suitable times to sow, and to plant out sweet peas. It is hard to beat sweet peas for colour, height and scent in a garden. Sweet peas like moisture and are best planted in an area not too dry. Sweet Peas are hungry plants, and adding lots of organic matter will improve the soil and help with moisture retention. I also add a mulch to help retain moisture, as dry ground is really not good for sweet peas. Sweet peas are time consuming to grow, but very rewarding. 

For tips about growing sweet peas including how to keep them flowering, and how to get straight stems and a video on how to plant and grow sweet peas.

Sweet Peas grown under glass in sheltered conditions need to be hardened off before planting outside. See how to do this below. Even though sweet peas are fairly hardy I would advise against planting out during a chilly spell, as this can knock back sweet peas (and any other young plants veg or bedding) Once Sweet Pears are hardened off, do not worry too much about the weather. Sweet Peas are half-hardy annuals and will tolerate a fair degree of chill.

A great summer annual is 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 garden centres. Cobaea Scandens is native to South America, it is tender (non hardy)and a lovely climbing plant to have as part of a summer display. The specialist seed catalogues have a fantastic range of seeds and it's 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. It is best to delay planting out until they are good-sized study plants.

Easy annuals to grow from seed that provide an equally bold splash of colour are nasturtiums, sunflowers, calendula and cornflowers. All are easy to germinate from seed and not as tender as Cobaea and Amaranthus.

A wildflower patch creates a splash of colour, and you don't need lots of room and time. There is a simple way to create a wildflower 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 weeds and the soil warm enough for germination.

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. 

Remember that the top growth on potatoes, the haulm, 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.

For April planting, it is important to distinguish between the hardy veg and the more tender. 

In sheltered areas in April, you can plant out the hardier vegetables: Broad beans, beetroot, carrots, Swiss chard, summer cauliflower, kohlrabi, lettuce, leeks, radish, turnip, spring peas and perpetual spinach.

Tender vegetables will need to be protected, which means germinated and grown under glass, in a greenhouse or conservatory. Tender vegetables include courgettes, squash, peppers, tomatoes, cucumbers, aubergines, celery, celeriac, French beans, sweetcorn and globe artichokes. Only plant out when the risk of frost has passed. 

To prevent leggy seedlings, which often happen when seedlings are germinated on a windowsill, you should physically turn the seedling container around each day. This is because when the light comes from one source on one side, i.e. a windowsill the seedlings will grow towards the light, which can make them leggy. Regularly turning the pot around helps to reduce this. 

April is also a suitable time to sow in the greenhouse, for planting out later, Peas, and 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 advice on growing peas and beans.  

The planting order for the bean family is: Broad Beans can be planted out in March/April as 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.