Sub-irrigated raised garden beds are known as "wicking" beds. This means they are watered from below - from a water reservoir in their base. If done properly they have an overflow mechanism and subterranean air reservoir.
A good blended organic growing mix "wicks" the water upwards. This supplies the vegetable roots with the air and water they need, without you needing to water them from above, and encourages deeper root growth.
It's good to include a blend of volcanic rock, coir and biochar to keep your vegetables supplied with the right amount of water and air they need, even when you are away on holiday!
Here's the top 5 reasons that vegetables love being grown in wicking beds!
1. Low Maintenance and Drought Proof
Wicking beds have a water reservoir, and preferably an aerated area in their base. They hold enough water to last weeks at a time, and they are topped by rainfall.
If it hasn't rained for a few weeks, they can be topped up manually simply by connecting a hose to their base for a few minutes.
When built well, wicking beds need only fortnightly watering in summer, and only monthly in winter.
A hose can even be connected to a timer, and beds can be connected together to overflow into each other. And because they are sub-irrigated, hoses can often be used during water restrictions.
2. Stronger Plants with Abundant Produce
Plants grown in wicking beds have deeper, stronger roots than those grown in the ground.
Unlike their ground planted cousins, the growing mix in a wicking bed is always wetter beneath the surface, even in hot weather.
This encourages deeper root growth, which gives better drought resistance, tougher plants, and greater stability. And because they always have water when they need it, they do not undergo any water stress, meaning they grow faster and stronger. Plants growing in wicking beds are therefore many times more productive than plants growing in the ground with shorter growing cycles, and higher yields.
3. Fewer Pests, More Predators
Because wicking beds water your veggies from below - the top of the bed is dry. Snails and slugs hate the dry surface – so you don't need to use slug pellets which harm wildlife and pets.
Beneficial predators can then move in, like this skink. She loves to snack on any flailing snails or slugs together with aphids & ants! Everything forms a natural balance, allowing your veggies to thrive like never before! And of course stronger, healthier plants resist other pests too.
4. No Digging, No Weeding
Raised veggie beds require no digging when you get the fill mix right! A rich organic blend of fill we that contains small pieces of volcanic rock helps aeration and prevent compaction. And adding some worms at the outset, or even installing a self fertilising worm composting module helps as the worms keep the soil nicely broken up, removing the need to dig.
Plants grown in wicking beds are lucky enough not to compete with Weeds. The weed seeds cannot germinate because the top of our bed remains dry. And even when it rains for extended periods, there are less weed seeds to germinate because no digging means no soil turnover.
5. Less Disease, More Vegetables
Fungal disease after rain or top watering can play havoc with tomatoes, cucumbers or zucchini planted in the ground. Wet soil and splashback onto leaves spreads disease to the lower leaves.
However veggies lucky enough to be grown in a wicking bed are irrigated from beneath, and therefore the dry surface soil between rainfall stops many fungal issues taking hold. And that means more on your plate! Ensuring the top of your beds are well mulched, helps to further prevent splash-back from rain passing any lurking spores onto the delicate leaves of your veg.
So there you have it - 5 good reasons to get a wicking bed installed today!
Contact Urban Veggie Crew if you'd like to find out how to get one installed in Sydney: www.urbanveg.com.au/contact-us
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