Need advice on soil prep

[Sheryl Gavin]

I've just moved into a new place with (yay) volcanic soil. No more sticky boggy clay! The previous tenant   kindly left behind some raised beds. I've grown veges successfully in the past but haven't paid any attention to the nutrients (or lack thereof) in the soil. How do I work out what nutrients are lacking? I have noticed an absence of weeds in the empty beds and wonder if that means the soil is "dead". Soil 101 hints and tips required please.

[Kelly Ronayne]

If the raised beds have been used in the recent past, weedlessness is probably just the last tenant being nice and leaving you clean beds. Raised beds in particular would suggest that somebody's been cultivating them!

Soil care absolute basics: add heaps of compost, if you're doing some digging over, try to avoid mixing the fertile top layer of soil (top 30cm or so) into the less fertile lower soil, and sow a green crop.

Green crops
A good combo is mixed seeds of a grain and a legume - my fav combo is oats and lupins, but other good crops include mustard, phacelia, broad beans, alfalfa, etc. Just remember that with a green manure you're not going to get a crop off it, so don't plant beans thinking you'll get a harvest of beans as well as soil prep - you need to dig the green crop back into the soil a few weeks before it starts to flower to get the best nitrogen hit for your soil. If you wait until the plants flower and start producing seeds, all the nitrogen and energy goes into the fruit production rather than your soil. A good way to tell when it's ready to dig in is to have a look at the roots - they should have bulbous little nodules on them that look pinkish and green when you cut them in half. Once you've chopped up the plants a bit with your spade and dug them back into the soil, wait for about 6 weeks or so for them to break down a bit before planting your next crop.

[David Earle]

That is great advice from Kelly.

You can added rotted manure with your compost as well to give it a boost.

A good sign of live soil is whether there are creepy crawlies in it - worms especially. Compost, manure and green crops will encourage them as well.

It is possible that your kindly previous tenants sprayed with Roundup (or the like). If so, that will take a month or so to disappear from the soil. But at this time of year there is not a lot of regrowth going on anyway.

[Sheryl Gavin]

Thanks Kelly and David, that sounds like really good advice and I'll follow it to the letter. Yes, I'd say a dose of Roundup had been administered although I've been here for 3 months now and still no sign of weeds. I'll have a dig around and see if I can find any worms. What type of manure is the best to use?

[David Earle]

the easiest one to find is sheep - which you can get as pellets from most garden supply stores - and it is high in Potassium, which is good for fruiting.
Horse, cow and chicken are all good. These are usually only available from the farm or stables. There are a few people on trademe that offer them. Just make sure it has had time to rot down before you put it near plants. Fresh manure can burn roots - especially chicken, which has lots of ammonia in it to start with.

[Sheryl Gavin]

Thanks David. if the manure provides the potassium what adds the nitrogen and other nutrients needed in the soil? Is a general NPK fertiliser useful to add to the mix or will that be too much if I put in loads of compost and manure?

[Flo]

Seaweed tea makes a great organic liquid fertiliser too. You need a bucket or barrel to soak the seaweed in and after a few weeks or months (obviously it gets stronger with time) you can take "tea" from the vessel to water your plants with. Best if you mix the tea minimum 1/1 with fresh water to dilute before applying it to your garden.
Replenish your "teapot" with fresh water for more brewing. It can be a bit stinky and is best if you cover with a lid whilst brewing. Plants thrive on it as seaweed contains oooodles of nutrients. Eventually you can add the seaweed to your garden as compost if it hasn't already liquified completely.
Some people say you should wash off any excess salt before you begin but I've never worried too much about doing that.
The link below also gives a manure tea recipe.
http://www.aselfsufficientlife.com/manure-tea-best-natural-fertiliz...

[Sheryl Gavin]

Thanks for the advice Florence. sounds like OOOOdles of fun.

[Michael Hogan]

What nutrients are in the soil, and what are available to plants are two separate issues. That is where calcium (lime) comes in. It assists the availability of nutrients to the plants by various chemical reactions in the wonderful soil web of life. Consider generous amounts of lime in your nutrient programme. I have found this crowd "http://www.environmental-fertilisers.co.nz/index.htm" has the best biologically sound fertilisers in NZ. They are located in Paeroa, but have retail outlets. Now is a good time (when it isn't too wet) to aerate and add your ferts now, giving some time to work into soil before spring planting...Happy growing