Juggling space for plants and softwood cuttings In the last blog I said I waited until July to plant out chillies and aubergines into my tunnel. To clarify I’ve only done that for the past few years. The change was due to lack of space in the tunnel in June because the early sowings (beets, early potatoes and lettuce) were not ready for harvest. There was no room for the summer crops that were going to be following them into that space. To give the beets and lettuce more time I repotted the chillies and aubergines into larger pots (30 cm +) and kept them in the cold glasshouse a bit longer. I added soil and garden compost to the mix. The tunnel has windbreak mesh at both ends to keep a constant air flow. This works fairly well in preventing botrytis (grey mould) which loves warmth and especially humidity. The tunnel is a bit cooler but there has been little disease.In previous years when the lettuce or beets were harvested, I rushed to fill the space they had occupied, putting the chillies and aubergines into the ground when they were a smaller size. If the spring harvest was early in June, or conditions were cooler, there was sometimes a check to the growth of the follow-on summer crops. By allowing the spring crops to get bigger before removal and the summer crops to get bigger in their larger pots before planting out, there was a smoother transition and better harvests. So that is why I am happy to wait until July if I can.At this time of year garden centres are again full of plants. How do you choose what to buy? Prices have risen owing to some supply issues and you do not want to waste your pennies. Keep in mind the style of garden you want. If you are buying a tree or shrub, bear in mind these have a stronger visual impact than a herbaceous perennial. The large woody plants and especially the evergreen ones will contribute more towards the style, so chose these with extra care. When you chose where to plant a tree or shrub, take time to visualize how they will look in 20 years. The label usually only mentions the size after 10 years, but trees and shrubs will keep growing beyond that time! Have you ever found a plant description that states the height will be between 1 and 6 metres? It’s a little frustrating, but it’s all to do with genetic differences and whether they thrive in the conditions they are planted into. Why not take some cuttings in case the plant fails or as a present for Granny? Propagation is a skill that needs a bit of practice, but it allows you to produce plants for little cost. That means you can experiment and if they don’t succeed or if they don’t fit with the overall style, try again. Be observant so you can learn what works and what doesn’t.At this time of year most shrubs are actively growing, and new shoots are elongating. This juvenile growth is very soft and sappy and is likely to root easily if you can keep it turgid (keep it full of water and stop it from wilting) until it roots. There are different ways of getting cuttings from stems depending on the plant and the shoot’s growth. Stem cuttings at this time of year are called ‘softwood cuttings’. Look for a healthy young shoot 10 – 20 cm long and free from pests and disease. Remove it by cutting just above the node on the stem of the mother plant (to stop die-back). The cut stems are delicate and prone to wilting. They need to go straight into a polythene bag. Keep the bag closed and out of direct sunlight. Back at the ranch, prepare your cuttings by trimming with a sharp knife just under a node. Nodes have meristem tissue, which can differentiate the new cells to become different plant parts (roots, leaves, stems). The cutting should be about 10 cm long. They can be shorter if you have a heated propagator unit. Trim off lower leaves allowing at least one pair to remain near the growing tip. Put the cuttings into a pot with a mix of half vermiculite (or perlite) and half compost. This is a standard cuttings mix which retains moisture but also allows for drainage. The leaves should not touch other leaves. Water immediately, label, and cover with a polythene bag. Place the pot in a warm, light place which does not receive full sun. Check that the compost retains moisture by lifting the pot to gauge the weight, and once a week remove the bag and turn it inside out to remove any excess moisture. Water at any point the pot feels light, or the compost feels at all dry as you are trying to maintain high humidity to maintain turgidity. But don’t let it become soggy. Why keep it turgid? All leaves have stomata, structures that regulate the amount of water in the leaf. Stomata close to save water loss from the leaves. But that means the leaf can’t take in carbon dioxide (another function of stomata) and that means it can’t photosynthesize. Photosynthesis yields energy and food for the plant, and it requires some light and enough water. We are aiming to keep photosynthesis going until the cutting can draw water and food up through its new roots. Wilting in cuttings is not a good sign but don’t despair. They may well pick up after a day or two.When there is new leaf growth you can be sure the cuttings have rooted. Harden them off gently to help them adjust to the world outside their bag. Make slits in the bag, gradually increasing the air flow and lowering the humidity. After a few weeks remove the bag.Leave the rooted cuttings until you see roots emerging from the base of the pot. Separate them carefully, as some roots are brittle, and pot them up. Water, keep them out of strong sunlight for a few days until the roots settle and start to draw up water. Don’t rush to plant them out. Keep potting them up until you have a good-sized plant. Small plants can struggle in the great outdoors so do not be in a hurry. A year or more may be needed. Have you seen some plants yellowing at the tips recently? I think this is owing to lower temperatures and the plants not being able to draw up enough nutrients (especially nitrogen) while they are in active growth. Many plant mechanisms depend on enzymes which don’t work as well in cold temperatures. These mechanisms need nitrogen. I apply a very small pinch of fish, blood and bone to my affected plants and keep the more tender ones a bit warmer. Repotting them into fresh compost can also help. Too much or too little water can also cause yellowing.It’s never a good idea to go mad with fertilizer. Nitrogen is essential as it encourages deep green leafy growth and elongation. But if you add too much you encourage soft and sappy growth which is a magnet for aphids. These little sap suckers are usually found at the growing tips. They multiply incredibly quickly. Too much nitrogen will also delay the onset of flowers and fruits, so your harvest will be later.Watch any plants that need tying in to supports and add new ties regularly. They can grow really fast in spring. If they are twining plants which wind around a support check to see the direction of twine as this can be species specific. They will refuse to wind clockwise if you try to encourage them to in the anti-clockwise direction. Wouldn’t we all?