Pricking out and pinching out

Pricking Out and Pinching Out

How to Make Your Own Horticultural Electric Blanket

The first layer on top of all of our wooden workbenches is a layer of polystyrene insulating tiles. These tiles push the heat back up into our plants and ensure that it doesn't leak out through the wood.

Next, we lay a horticultural electric blanket on top of these tiles. You will only be able to use one of these if you have electricity in your greenhouse. We then layer capillary matting on top of this, followed by our seed trays.

This system helps to promote quick root growth and germination rather than heating the air around the plants, which is less efficient and much more expensive.

Of course, your seedlings will still germinate without a horticultural electric blanket, but providing them with a heat source at the base will ensure they develop strong root systems.

Pricking Out Salvia viridis 'Blue Monday'

Salvia viridis 'Blue Monday' is a hardy annual and can be an excellent filler plant in bouquets. It flowers from May until September and has stunning blue bracts, which make it a wonderful foliage plant.

Do watch out though, because Salvia viridis will self-seed, so make sure you have it in a spot where you are willing for this to happen, or happy to weed them out if you no longer want to grow them.

When your plants are ready to prick out, move them into small individual pots. If you put them in pots that are too large, they won't be happy, when they are young they like to be contained before they are ready to be planted out.

When it comes to hardy annuals, we tend to plant them out here from mid-April, but if the weather is particularly mild then we might plant them out a little earlier in the season.

With half hardy annuals on the other hand, these can't be planted out until you know that local frosts are definitely over.

How to Prick Out Your Plants:

• lift your plants from underneath with a pencil or plant label
• gently tug at the first set of leaves from the base until loose
• place your seedling in the centre of its new pot
• firm in with more potting compost.

Pinching Out to Create Stronger and More Productive Plants

Pinching out your plants will make them stronger and more productive growers and flowerers. You can do this with just about all hardy and half-hardy annuals, it's not just sweetpeas.

We tend to pinch out our plants after they have developed three full sets of true leaves. Once these have developed, pinch out the next set of leaves or the growing tip with your fingers.

Your plant will now start to branch out from all of its axillary buds, including the ones forming in the leaves below. This will help your plant to become a rugby player instead of an athlete. By this, I mean that your plant will develop into a short and stocky plant with lots of strength and multiple branches, rather than a tall plant which only has one flower spike.

When you then go on to cut your flower stems, always cut above a pair of leaves and this will promote further axillary bud formation within the plant. By picking flowers in this way, you will create more growth and flower formation, as well as strong root growth which you need for healthy plants.

Pinching Out Sunflowers

The same method applies to sunflowers as it does to other hardy and half-hardy annuals: pinch out the tip once three sets of true leaves have formed.

Sometimes it can seem a bit cruel to pinch out sunflowers as they can look a bit thin and spindly when they first develop, but you must do it. Pinching out your plants will help them to grow into strong and sturdy individuals and give you more flowers than you would get otherwise.