Renewing the nursery with green manure

It might seem a bit late to be putting in a spring green manure, but better late than never, right?

Sas figured out what seed we would need and how much, and I ordered it, and we were hoping it would arrive before all the lovely rain, but alas I was a bit late getting the order in, and we missed the boat.

The rain came and went, and the weather  seems to have settled into being consistently hot and dry now, but our soil desperately needs some love and attention, so we decided to go ahead and plant it anyway and rely on irrigation rather than rainfall to make sure it grows.

Here’s what’s in the green manure mix:

  • buckwheat
  • mung bean
  • French white millet
  • kidney bean

To make the seed easier to spread, Sas put it all in a bucket that was half full of clean sand…

and gave it a really good mix…

before spreading it. The area had previously been dug up with the rotary hoe and raked, and then Sas used the back of the rake to make a series of ridges down the rows to catch the seed as she distributed it. This method makes it a bit easier to lightly rake the soil back over the seed.

So, why a green manure? The nursery has three separate patches on the farm, and because of the nature of how a nursery works, each patch can stay in production for up to three years. But also, each year we need somewhere to plant seed and cuttings to grow new rootstocks.

To stop the soil becoming more and more depleted, we need to put some organic matter back into it, because the only input we routinely use is a bit of compost.

Unlike the orchard where ground cover is encouraged, the nursery is kept free of weeds to reduce competition for the baby trees, so it’s really important to keep the soil fertile by adding extra organic matter.

A green manure is the perfect way to do it—even if mid-summer is not the perfect time! Our seed mix included mung beans to add nitrogen to the soil and build organic matter, buckwheat for fast growing bulk and phosphorus accumulation,  French millet because it’s a fast-growing grass that combines well with legumes, and kidney bean because it’s another nitrogen fixing legume.

Luckily we have the benefit of an irrigation system already in place, so we’ll use a bit of water to get the seeds up and established, before we turn them back into the soil to work their magic in autumn, ready for planting next winter.

Tiny, annoying Rutherglen bugs

A couple of years ago we (and everyone else trying to grow fruit on the east coast of Australia) had a plague of these tiny bugs—have you seen them on your fruit?

They’re called Rutherglen bugs. They are tiny and a nuisance, and unfortunately there’s very little you can do about them. They’re a sapsucker, and if there are enough of them they can suck the juice out of your fruit and cause it to shrivel up.

The year we had a plague, some of our peaches had so much juice sucked out that they weren’t usable, but most were. The bugs can leave a slightly sticky residue on the fruit as well, but this washes off.

Interestingly, we’ve barely seen them since, which is often the way with ‘plagues’—they’re really just the result of an imbalance in the ecosystem that has temporarily favoured one insect over another, but they usually quickly get back into balance and numbers go back to normal (i.e., hardly , any).

Why does this happen? Mainly because they have a lot of predators, and nature tends to get these population explosions under control all by herself, as long as we have decent biodiversity in our gardens, and IF we don’t mess things up by using pesticides.

But, in the meantime, when you are experiencing an outbreak it would be nice to protect your fruit, right?

 

There’s a few things you can do:

  1. Hose the tree when it has a large swarm of bugs on it. This should discourage the bugs on the tree at the time, but if there are lots around in the garden the tree will probably be re-infested;
  2. If you have chickens or other poultry, confine them to the area around your fruit trees if possible – they will make short work of the bugs but, as above, if there are lots of bugs around, the tree may be re-infested when you
    remove the chooks;
  3. Protect the tree with a very fine net—the same sort you would use to prevent fruit fly getting to the fruit (because as you can see in the photo below, they easily get through regular size bird netting);
  4. As an absolute last resort, you can try a home-made organic spray, but be very careful if you do this, it’s easy to do more harm than good by accidentally killing the predator insects that will be eating the Rutherglen bugs, and you may just be perpetuating the problem.

So, the key message is don’t worry too much about them as there’s little you can do!

Concentrate instead on the long-term solutions for these bugs and all the other pests as well, which are (1) continuous soil improvement, and (2) continuous biodiversity improvement. In our experience if you stick to those principles, most problems like this are short term.

We go into more detail about the lifecycle, identification, prevention and treatment of Rutherglen bugs and 14 other common pests of fruit trees (including some recipes for home-made sprays) in What’s Bugging My Fruit?

 

There’s slugs on my fruit trees!

Have you seen these critters on your fruit trees?

These are pear and cherry slugs, and as you can see, they eat the leaves on pear and cherry trees.

The first question to ask yourself when you see these creepy looking slugs (as with all pests and diseases on our fruit trees) is, how much damage are they really doing?

One of the advantages of keeping a close eye on your trees is that you will often notice problems as soon as they occur, and can then take simple action, like squashing the slugs between a folded leaf.


In a normal season, this particular pest will go through at least two life cycles, so the more of them you squash as soon as you see them, the more you interfere with their natural life cycle and can prevent numbers building up.

Fruit trees can actually tolerate quite a bit of damage without losing function or growth – our rule of thumb with pear and cherry slug is that if a tree has lost more than 30% of its leaves, that will be our trigger to treat them, and in all our years of growing, we’ve closely monitored every year, and never had to take action against them.

Usually what we find is that if we are patient, a predator insect will come along and do our work for us, leaving behind a dry, parasitised slug as you can see on the leaf below.

So pear and cherry slug is a great example of learning how to watch our trees and learn what’s really going on, rather than assuming that if there’s a bug, there’s a problem!

If you want to find out more about the life cycle of the pear and cherry slug, and how to treat and prevent them, check out “What’s Bugging My Fruit?“.