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How To Improve Poor Soils and Grow the Best Vegetables (or anything else!)

It is a fact that successful gardens are determined by the quality of the soil you plant into. Generally the less you work your soil, the poorer it becomes particularly if you are trying to garden on clay or in fine dusty dirt. And now that the craze for gardening has become focussed around food-growing this has become more important than ever.

So how do you improve your soil?

The best way to start is by testing the soil: Make sure you've got sunshine over this area for at least half a day. Grab a handful of the existing soil, squeeze it in your fist and relax your hand. Take a look at it. Can you crumble it evenly through your fingers, is it pouring away in fine granules or has it remained mostly in a ball?

A good textured soil is the first crumbly one - the roots of your vegetables will have plenty of opportunity to grow through this evenly blended soil. But if it broke up into fine particles and literally poured away then you've got too sandy a texture - it will dry out quickly and it needs more organic matter to give it structure. The third possibility - the ball-shaped soil - is too heavy and moist; the soil isn't draining freely and it's probably a clay-based garden. Clay is often good for nutrients, but its denseness means it needs help to un-lock them to the plants.

As a new gardener or home-owner you often find your soil falls into the latter two categories, so the best thing you can do is add organic matter in the form of Living Earth Organic Compost and dig it through the garden to a depth of 30 to 40cm. This is the optimum depth for a season of vegetables - digging further, especially in clay soils is likely to bring up highly compacted soil that will not assist in the growth of vegetables.

Depleted soils are common in NZ, through intensive use of our soils, removal of topsoils during building and renovating and a general disinterest in gardening and composting over the past decade. The constant use of chemical fertilisers in growing does nothing for soil structure and so it is important to begin by adding back composted organic matter that will bring earthworms - a gardener's delight. Earthworms create tunnels in the soil that improve drainage and improve its structure very quickly. They feed on the organic compost and their casts improve the friability of the soil. They work best in moist soil beds.

In the case of sandy light soils adding the compost means that the heavier compost particles will attach to the lighter dirt and assist in holding moisture and offering more trace elements than previously available.

For clay soils the compost will break up the lumpy clay particles and assist drainage as the water will be able to move more freely through the soil. Make sure that your clay soil is not waterlogged when digging it over, as this can lead to compaction of the earth particles - the very structure you are trying to lighten.

Living Earth Organic Compost available from Central Landscape & Garden Supplies yards is made from recycled organic green matter and is 100% free of weeds. Living Earth Organic Compost meets the NZ standard NZ4454 - an assurance the compost is of extremely high quality and in the composting process the organic matter has been fully matured and can be safely handled as you dig it through your garden.

How much to use? When digging compost through your soil, a cubic metre will generally be worked in over a 5 or 10 square metre area.

When do I use Garden Mix?

If you have decided to garden in raised beds, there is an advantage in this - plants and their roots often benefit from the extra warmth at elevation. For such intensive gardening the best option if to use a planting mix which you can plant straight into. In this case make sure that you fill these beds with Living Earth Garden Mix (OR Living Earth Organic Veggie Mix) - this contains compost, but is blended with fillers such as bark fines and pumice, as well as fertilisers and is also 100% weed-free. Remember that raised garden beds will need to have compost added to them regularly (annually) to retain structure and nutrients.

Living Earth Garden Mix can also be use to layer on top of existing gardens instead of digging through compost. It is a very easy way of topping up soil levels without the necessity of digging.

Working Compost or Garden Mix into your home gardens is the best way to have a successful garden - vegetable or ornamental.

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