Most years we have your seedlings fully ready for transplanting, but the cold weather this past week has made it impossible for us to have your seedlings fully hardened off. What does hardening off mean? It means helping your plants transition gently from the protected culture of the greenhouse to the raw elements in your garden: toughening them up for life outdoors. Plants need some time to get used to UV and wind so they don't get sunburn or wind damage. What to do?
- Give them a few hours a day outside getting used to direct sun and breeze, increasing their exposure over a few days before planting them out. You will be able to see their leaves and stocks thicken!
- If you REALLY want to put your seedlings direct in the garden, offer them a bit of shade for ½ day at a time for a few days - especially if you have full sun.
- Cover them up if the night time temps drop below 10C for the first few nights out
How deep should you plant?
- Plants have grown their above and below-ground parts exactly where they want them, so plant to the same depth they've chosen. BUT do make sure you've brushed a bit of garden soil over top of the potting mix around the roots so none of it is exposed. It will dry much quicker than the surrounding soil as moisture is wicked out by sun & wind, which could result in your new seedlings dying of drought even if the soil is wet.
- BURY TOMATOES DEEP!! Any buried part of their stalks will grow roots underground! We snip off at least half the leaves, dig a trench that angles downwards, and bury all but the top tuft of leaves. They'll look small but they'll be ever so much more drought-resistant, and once they've got those roots established they'll grow FAST.
Leggy plants...what to do??
- For tomatoes, see above. For most other plants with long stems, plant on an angle so the stem lays more horizontal than vertical. It will bend towards the light and straighten out, but in the meantime there's a lot less danger of it snapping from wind, animals, or wayward human traffic.
- If planting on an angle isn't an option, you can always stake your plants temporarily until their stalks thicken up.
Give them some food to help stimulate strong root development
- Fertilizers high in phosphorous are especially helpful - e.g. bonemeal or an organic transplant or 'root zone' fertilizer. Liquid fish is good at transplant time. A shot of compost in the hole helps too!