Spring has sprung in most parts of the country so its time to get those vegetable seedlings started for the upcoming summer months....
Some seeds germinate quite easily with little fuss and bother. Carrots, Beetroot, Peas, Beans, Onions, Lettuces and all those Brassica can be sown directly into the garden at quite low temperatures. Anywhere over 12 to 15 degrees C and they’ll eventually appear with their first leaves. It’s those varieties that require a bit more heat that growers get frustrated with, even going as far as blaming the seed! Can you believe it!
Yet a simple technique will vastly improve your strike rate and give you a head start while Mother Nature warms up outside.
The two main groups of vegetables that fall into this category are the Solanaceae family (Tomatoes, Peppers, Eggplants, Tomatillo, Cape Gooseberry) and the Cucurbit family (Cucumber, Zucchini, Squash, Pumpkin, Gourd, Melon and Watermelon). All of them require heat but not necessarily light to germinate. This means that, if you have a hot water cupboard at home, you automatically have a very good germinating space on hand.
Not all Cucurbits will tolerate cooler outside temperatures as seedlings, so plan on sowing your Cucumbers and Zucchini first (in one tray) along with another tray containing your Peppers, Tomatoes and Eggplants. These will be your initial sowings to be followed a month later by another tray with your Pumpkins, Melons and Watermelons.
Melons and Watermelons, in particular, don’t like the cool ground and low night temperatures and won't thrive until these warm up. If you want to plan a bit ahead for them, dig in some extra compost into the space where they’ll eventually grow. It could possibly be a dry summer when they’re just starting to fill out and well composted mulch is well known for its moisture retention properties.
Here’s what you do so that you don’t take up too much space...
- Sow your seed in lines in a tray as you normally would marking with a small stick for each row. Water the tray so that it's fully moist right through, then wrap it with plastic cling film quite firmly so that a gap is present above the top of the tray.
- Always use a good quality FRESH seed raising mix, resisting the urge to use last year's bag or to blend it with potting mix, compost or garden soil to make it go further.
- Place it in your hot water cupboard (preferably above the water cylinder) and keep the cupboard door closed as much as possible to keep the heat in.
- After 5 days, take a peek to see if they’re coming along. You’ll be amazed how many have germinated. They’ll look quite pale as, without light, they’ll have been unable to photosynthesize and form the green pigment Chlorophyll but this will happen within a day or so of being exposed to sunshine.
- Remove the tray before the seedlings press against the cling fill and start to stretch. Even if they haven’t all germinated, they will have broken dormancy and won't be far away from sprouting.
- Keep the tray as evenly warm as possible, perhaps putting it in a sunny position during the day and bringing it inside at night to keep its average temperature up.
- Transplanting seedlings should be done when the cotyledon leaf is well formed which indicates that the root underneath is a decent size.
- It's best to transplant seedlings into a shady spot when it's cool, as direct sunlight or hot temperatures could cause them to wilt unnecessarily.
- Let them stand up and start to develop a bit more before hardening them off in the outside world, seedlings are still at their most vulnerable stage now.
Around Labour Weekend, sow your Melons, Pumpkins and Watermelons, this isn’t too late. In fact this later sowing will catch up to any earlier sowings by growing faster.
Then, to keep a continuity of Cucumbers, Tomatoes and Zucchini coming along, about mid-November sow a second batch of seed. This way, you'll have a harvest right through the summer months. And don’t forget to plant them out into ground that’s been well composted to help with moisture retention.
Late sowings of Tomatoes will quite happily bear fruit into the autumn months and don’t mind the nights getting cooler or the days shorter.