Our frequent rainfall keeps Ireland green and beautiful. However, since you’ve put up a tunnel and blocked it out, now it is up to you to keep your plants hydrated!
Water, along with oxygen, sunlight and soil, is a basic need of all plants, even though their requirements can vary considerably. From one type of plant to another, from tiny seedling to full-grown, from pots to open soil, and from overcast days to sunny ones this job can keep you on your toes!
There is no correct answer to this, but you want to keep your plants somewhere between waterlogged and parched! If the soil feels dry below the top inch or two, it is probably time to water. If plants start to droop or lower leaves begin to yellow they are too dry. When you see moulds and mildews appearing on the soil surface, it is likely too damp. Intuition for this develops quickly enough.
Morning vs. Evening
This is a point of debate. Most everyone agrees that in the heat of the day is not the best time to water. However, if a plant is wilting or is a tiny seedling drying out, it is always better to water than let the plant suffer damage or death. The advantage of evening watering, particularly in very warm weather, is that the moisture can be retained overnight and will evaporate the next day once the heat soars again. The advantage of morning watering is that if you have a hearty nocturnal slug and snail population you can discourage them from slithering along on moist soil munching all of your plants overnight by keeping things at their driest then.
Manual vs. Automatic
This is another point of debate and probably something in between is ideal. Automated systems can be put on a timer and adjusted throughout the season. This is ideal to cut down on time and effort, but it is always wise to monitor the situation and not fully depend on automation. Manually watering allows you to reach every plant and give more or less in specific situations, but it does require a dedication of more of your time. Polydome does supply irrigation equipment, including simple battery-powered automatic timers.
Overhead vs. Underneath
Overhead watering, including overhead irrigation lines and the use of a hose, does have the advantage of washing down leaves like the rain. However, some plants work better with underneath watering, from watering a tray under a pot to using capillary mats or low-level drip lines. Reason for this vary, but this often suits plants that are prone to mildews or blight from remaining damp or leaves that scorch from being watered in the sunlight. In a protected structure where there can be less natural wind and ventilation, this is often an ideal solution. An example of this is using low-level drip lines for tomato plants to avoid blight or feeding potted cyclamen from a capillary mat to keep their leaves healthy.
In the winter, having a roof that keeps excess rain out is a great advantage to many plants. However, the surrounding areas outside the tunnel moisten the areas near the edge, so this is something to bear in mind.
So, the next time it rains, enjoy the raindrops! They are little droplets supporting life!
It’s March and high time to start some seeds! Here are a few tips for success.
1)Unless you are sowing directly into the soil, having a bench that is the correct height is a must. This saves your back and also allows you better precision when sowing tiny seeds that are difficult to see.
2) Next, follow the instructions on the packet. Not all seeds are sown in the same way.
3) There are several factors involved in triggering a seed to germinate. These include light, temperature and moisture. At this time of year, the temperature is too low for certain seeds, so using a heating mat or heating cables in sand can speed up germination, resulting in a stronger plant.
4) It is a good idea to label everything clearly as you go along. This can avoid confusion later on when the little darlings start to emerge and you don’t know who is who! It is also a good idea to record when and what you sow in a notebook or diary for future reference.
5) A seed is a tiny miracle that contains everything it needs for life. However, once the outer coat has been broken down, the emerging seedling is very vulnerable until it has formed sufficient root to acquire moisture and nutrition for itself. At this stage it is vital that it isn’t allowed to dry out. Here are some ways to ease your seedlings through this delicate stage:
*Pre-water the growing medium well.
*Partially cover seed trays with polythene or glass (allowing some air flow) to retain moisture.
*Gentler forms of watering such as using a watering can with a rose, overhead irrigation, drip lines or capillary matting are preferable to using a garden hose on young plants. (Of course, the more vigorous plants like peas and beans will withstand much more than a delicate cactus seedling.)
6) Did you know that keeping your young plants up on shelving isn’t just for convenience? It also serves to protect them from pesky mollusks. Yes, slugs and snails. They love damp, dark corners to hide in during the day, saving their energy to come out and graze all night. So, keep your root babies as far away from them as you can!
Best of luck to everyone who is setting out to sow seeds for the first time or the 50th time!
Most people plant onions as sets; semi-mature bulbs which will hopefully grow bigger and be harvested before they go to seed. But you can also raise onions from seed sown in your greenhouse instead of from sets planted later. This is especially useful on cold, wet soils or in cold, wet springs, as onions cannot tolerate those conditions. Seed-raised plants are cheaper than sets, you have more varieties to choose from, and the plants are less likely to bolt or be pulled out of the ground by birds. On the downside, seedling onions need a longer growing season so February is definitely the last month for sowing, and the longer growing season means more time for pests and diseases to attack them.
Sow the black, angular seeds thinly in a seed-tray, or in modules at up to five seeds each. Keep them at about 10-15°C. The seedlings come up in loops, and you should prick them out from seed-trays into pots before they pull their tips out of the compost and straighten up. If multiple seedlings come up in modules, either leave them to push each other apart later as they grow, or single them with a fine-pointed scissors to give the one remaining plant room to grow a bigger onion. Keep the compost neither bone-dry nor saturated. Grow on the plants in bright, cool conditions until they have two or three leaves, harden them off well and plant them out at about 15cm apart each way. Wider spacing gives you bigger bulbs, and tighter spacing gives smaller ones.
You can also plant sets in pots and give them a head-start under cover, planting them out only when conditions improve.
Basil is easy to buy from the shops, but you can grow a wider range of types yourself at lower cost to you and the environment. The type sold in non-returnable pots is usually sweet basil suitable for salads and pesto, but there are also cinnamon and lemon basil, varieties with purple leaves that look great in green salads and spicy or liquorice-flavoured Thai varieties that combine well with Asian food.
Basil is a fast-growing, tender annual that needs lots of light, heat and water. Being very sensitive to cold, it is an ideal candidate for tunnels and glasshouses, especially in our unpredictable summers. It improves the flavour of tomatoes when served with them, and some say that it also does so when grown with them. It grows best in well-drained acid or neutral soil. Sow a succession of crops, but just a couple of plants each time is enough for regular use unless you want extra for pesto. Either sow them in cell-trays or in situ in the greenhouse soil, thinning them to single plants as soon as they are big enough to see. Use a scissors to avoid root disturbance. Thin or place the plants to about 30 centimetres apart. Harvest leaves as soon as the plants are about 20 cm tall, by cutting off shoot tips. Leave on the lower leaves until you discard the plant; they will produce the food to grow new shoots from the lower side-buds. Even if you need no basil, cut off the tips to prevent flowering (which makes the leaves bitter) and encourage fresh sprouts to grow. Surplus leaves can be either frozen for later use or composted, and the flower-buds are edible too.
You can grow sweet corn outdoors in a good summer, but for a more reliable crop you need a greenhouse. April sowings are best done in pots but in May and June seed can be sown directly into its final position. Sow one fresh seed about 1cm deep per tall pot of free-draining compost: if using older seed sow multiple seeds per pot and single the seedlings later with a scissors. Keep the compost warm and not too wet. Sweet corn roots go very deep and do not tolerate confinement, so plant out your crop as soon as possible. Choose the tallest space available, although it won’t matter if the tops are bent over at the roof. Dig large planting holes 30cm apart in a square block to aid pollination. Fill them twice with water and add in some compost when planting; corn needs plenty of water and feeding.
If space is short, you can plant corn between rows of greens due for harvesting soon. Keep watering and feeding. When the sticky tassels appear on the lower female flowers, shake or tap the plants gently each day to shower pollen down from the male flowers above and ensure well-filled cobs. Cross-pollination gives poorly set and less tasty cobs, so if growing different varieties try to plant them as far apart as possible. The cobs mature close together, so sow later crops to extend the season. The cobs are ripe when the tassels darken and wither, and punctured kernels leak milky fluid. They dry up and get starchy very soon, so harvest them promptly, cook then immediately for four minutes in boiling water, and enjoy.