The three biggest challenges at this time of the season are to keep the seedlings and young plants in:
- Enough light
- Enough warmth
- Fed (keeping up their immune system)
Did you know that seedlings need more hours of light than mature plants! We aren’t talking about intensity of light (blazing sun) but hours of light to stop them from becoming leggy.
A challenge for those who sow early is to stop seedlings from becoming leggy.
This can be done in two ways … reduction of water/moisture to slow growth down or artificial lighting.
Giving the minimum amount of water
This is a bit of a balancing act but OK if for short periods. Growth slows and there is a danger of plants wilting. However, if you aren’t out all day, you can keep an eye on them and mist them should they be desperate for a drink!
Seedlings prefer the blue at 6400k – I use a CFL bulb a lot on my seedlings when light levels are low.
You don’t need a high wattage if you only have a few seedlings. Even a 25 watt is useful – just keep the light low over the seedlings and use a reflector – kitchen foil will do!
It’s now the beginning of May and the weather in the UK is about to drop to freezing temperatures at night.
Although many of my plants are in the polytunnel, I’ll still fleece them. This helps keep the condensation off their leaves as well as the temperature a degree or two higher under the fleece.
The best place for young plants is still inside the house, or if you can afford it, a heater in the greenhouse/polytunnel.
The idea of having the soil nutrient contents on the side of a grow bag is a distant dream – including NPK plus micro nutrient levels.
Until then, we’ll just have to guess “what lurks inside” and add the nutrients that will benefit our plants.
The problem is though, unless temperatures are reasonable, plants won’t feed anyway!
A way to give them a boost when the weather is cold, is to foliar feed at the warmest time of the day (though not in direct sunlight) in order to keep their immune system up and running.
I give my seedlings a misting with a tonic such as liquid seaweed, SP plant invigorator and there are many hydroponic boosters (including organic ones) that can help plants through the hard times.
In cold, damp and wet conditions, plants will soon be affected by fungal, bacterial and viral diseases so the challenge is to ward them off. This is difficult to do if the weather has been and remains dull, damp and cold.
To sum up
To stop them becoming leggy: under-water or use a compact florescent light.
Avoiding the cold and damp: fleece them, even in the greenhouse, and keep the condensation under control by keeping the air circulating – better still, keep them in the house where the air is less humid and less damp.
Give them a tonic: a foliar tonic/boost applied at the warmest time of the day can help keep their immune system up and your plants healthier.
Whatever you do, it’s a challenging time … let’s hope the weather improves soon!
If you have any tips that you would like to share, please mention them below.