Will a multigraft fruit tree suit you?

Multigraft fruit trees are kind of awesome.

A multigraft apricot tree with two varieties
A multigraft apricot tree with two varieties

This is a great example — an apricot tree with both Katy and Trevatt apricot branches. Katy is an early apricot that is a bright orange colour, firm texture, slightly oblong shape and terrific flavour that combines sweetness and tartness. It’s also a reliable cropper.

Trevatt is a more common apricot that you may have heard of — it’s a heritage variety (dating from the 1900s, developed in Mildura), and is completely different to Katy. It ripens about a month later, it has pale lemony-orange skin, and is a super-sweet apricot with very little tartness. It also has a much different texture, ripens from the inside, and is much softer — it can even go a little mushy if allowed to get overripe.

So, will a multigraft suit you? They’re much less well-known, and many gardeners are a little hesitant to try them out.

It’s almost a no-brainer that a multigraft is a better use of the space in your garden, unless you have space for a LOT of fruit trees and would prefer to have whole trees of each variety. Considering that a mature tree can easily yield up to 40 or 50 kg of fruit (or more) in a good season, it usually makes sense to spread the harvest over a longer period, rather than have a massive glut to deal with all at once.

There’s a couple of other great reasons that multi-grafts can work well:

  • pollination: in this example both varieties are self-fertile, but even self-fertile trees can benefit from having pollen from another variety close by, and this can help to increase yields;
  • spreads the risk: apart from the issue of gluts already discussed, some seasons just don’t favour some varieties. For example, if you happen to get a frost just at the time when the Katy are at full bloom, the Trevatt may be later coming into bloom and might therefore have less frost damage. Another scenario we’ve seen many times is rain affecting one variety that is almost ripe, causing it to split, while another variety that is still a month away from picking can escape relatively unscathed — so the more varieties you have, the better your chance of at least getting some fruit every year!
  • disease resistance: different varieties may be more vulnerable to particular diseases, like blossom blight or brown rot, either because of the difference in their ripening times, or just the natural resistance of that variety.
A fruit salad tree with a plum and two apricots
A fruit salad tree with a plum and two apricots

A fruit salad tree is like a multi-graft on steroids!

This extends the concept to include different types of fruit on the same tree, rather than just different varieties of the same type of fruit. In the example we’ve included here, you get both!

This tree has three varieties:

  1. Katy apricot (described above) – ripens late Nov
  2. Trevatt apricot (described above) – ripens late Dec
  3. Angelina plum – an early season European plum, very sweet, with beautiful dark purple skin with the traditional dusty-looking ‘bloom’ on the skin. These plums are incredibly delicious and versatile – you can eat them fresh, dry them, bottle them, jam them or make them into wine, just to name a few. They’re also a favourite for the classic European plum dumplings, or plum cake. They’re a really good plum to include in the garden.
Beautiful Angelina plums
Beautiful Angelina plums

Angelinas ripen in January – so with just one tree you’ve already extended your harvest over three months, as well as given yourself a pretty good variety of fruit to enjoy and preserve.

We love creating multi-grafts in our on-farm nursery (called Carr’s Organic Fruit Tree Nursery), and have quite a lot of different combos on sale this year — you can see our selection of multi-grafts here.

At the moment we’ve limited it to apricots and plums (though we have plans to extend it to apples, pears and peaches), but there’s heaps more you can do in your own garden, by learning how to graft new varieties onto existing trees.

It’s such a brilliant and easy way to extend your fruit season and increase the variety of fruit in your diet that Grow Your Own Fruit Trees for Free
is one of our favourite short courses, and probably the best one to start with if you’re new to grafting. We also have specialist courses on individual grafting techniques when you’re ready for them.

There can be a couple of drawbacks with multi-grafts though.

One of them is that the trees can come out of the nursery a slightly unusual shape (as you can see from the photo above), and so require a bit of careful management to establish as a useful ‘vase’ shaped tree.

The other main issue is that one variety may dominate the tree, and again, may need some attention when pruning to help keep the tree balanced. A handy tip is to plant the tree with the weakest branch pointing north, where it will be favoured by more sunlight.

But really, the management issues are usually handled easily during the regular “getting to know you” phase of your relationship with the tree, and once established, they usually settle down and crop beautifully.

Should you spray organic fungicide in autumn?

A peach bud in spring with copper spray
A peach bud in spring with copper spray

A lot of people don’t think “organic” and “spray” go together, but actually there’s a couple of relatively ‘safe’ sprays that certified organic growers can use, under strict organic standards.

The only sprays we use are organic fungicides — a little bit of copper, and elemental sulphur — because in a wet season they can make a huge difference in preventing some particularly nasty fungal diseases if you use them in spring.

An apricot with brown rot
An apricot with brown rot

Some people also recommend spraying fungicides on fruit trees after the crop has been picked in autumn, to clean up any residual disease, but this is a bit more controversial.

So, when is the right time to spray? Do your fruit trees really need an autumn fungicide?

The answer is … sometimes!

In our short course Keep Your Fruit Trees Free From Disease we detail those diseases that can benefit from an autumn spray of an organic fungicide, under certain conditions, like brown rot.

So we certainly don’t rule it out, and it can be a useful part of an overall strategy for cleaning up some diseases. However, in most reasonably healthy trees, you don’t need to routinely use a fungicide.

And that’s a good thing, because even organically allowable sprays can have an impact on the environment, particularly the soil, and you should only ever use the minimum amount necessary, and strive instead for a really rich biodiverse garden where natural immunity will be at its highest. (And you should never use chemical fungicides.)

If you’ve had a dry season – as we have in central Victoria this year – there’s been very little fungal disease.

Remove this diseased wood when pruning for good disease control
Remove this diseased wood when pruning, for good disease control

Under these conditions our strategy includes pruning any diseased wood out of the tree, and totally removing it from the tree and the orchard floor, but we won’t be needing to put on a spray at all. Excellent!

Is rain good for fruit?

A lemon covered in raindrops
A lemon covered in raindrops

As a fruit grower, lying in bed listening to rain on the roof can bring up a wide range of emotions, both good and bad. In our typical dry summers most people welcome rain when it comes, so it never seems appropriate for us to express concern about the damage it can do to fruit. However, it hasn’t rained for a while, so this week we reflect on the question – “Is rain good for fruit?”

Like everything in farming, the answer is complicated, and depends on lots of different variables, so let’s break it down a bit.

1. Trees like rain better than irrigation waterup to a point! As a gardener, you’ve probably noticed how “perky” your garden looks just after rain. One of the reasons (apart from the leaves being cleaner) is because the rain carries dissolved nitrogen which is easily absorbed by the plants, giving them a nutritional boost. Too much rain, however, and the soil can become waterlogged, creating anaerobic conditions, which actually stops the plants’ roots being able to take up nitrogen! The other advantages of trees receiving their water from rainfall (rather than irrigation) are that the entire root system gets water (rather than just at the point of water delivery), and if you’ve been keeping your garden on rations due to dry conditions, they just love the opportunity to get their fill of water for a change!

A fungal disease outbreak on an apricot
A fungal disease outbreak on an apricot

2. Rain can trigger fungal disease. One of the biggest pest and disease risks in an organic farm (or garden) is fungal disease, and nearly all fungal diseases are triggered by wet conditions (at the right temperature). In general terms, the more rain, the more fungal disease. This risk is highest at the beginning of the season (i.e., at flowering time in spring), and then gradually decreases as the season progresses. During autumn, if the summer has been generally dry and there is not much fungal disease around, the risk of a new fungal outbreak is relatively low.

Cherries that have cracked in the rain
Cherries that have cracked in the rain

3. Rain can cause physical damage to fruit. This is very specific to the type (and even variety) of fruit. For example cherries are particularly vulnerable to splitting from the rain, and some varieties of apricots also split easily. Hardier fruit like apples and pears, however, rarely experience physical damage from rain.

An apricot with a severe crack caused by rain
An apricot with a severe crack caused by rain

4. “Hard” rain can damage all fruit. Storms that bring rain often also bring hail, and that can be completely devastating to all fruit. Hailstorms are very random and localised, so it”s pretty much the luck of the draw with this one, though if you live in a hail-prone area, netting can definitely be your saviour. All fruit are vulnerable to hail damage, including apples, pears, plums and quinces.

5. Rain is good for the landscape. When you’re trying to grow food in an arid landscape (as we are), the general impact of rain (as long as there’s not too much, or too quickly) is generally FABULOUS! It fills water storages, keeps the bush alive, helps to sustain our farming communities, and helps backyard fruit growers maintain their own food security. We love it….except…. when there’s too much! If rain becomes flooding and the soil becomes saturated for too long, it can lead to ALL sorts of problems! Anaerobic soil conditions, trees dying, waterborne soil disease, nutrient leaching, dams breaking their banks, and the list goes on. We’ve seen it before when the drought broke in 2010/11.

A rainy morning and green grass
A rainy morning and green grass

6. Rain is good for mental health. It’s a generalisation, of course, but very often rain can be a huge relief to farmers and others in the community, especially if it is relieving the pressures of trying to farm in a dry landscape, though as you can probably see from our list, it totally depends on the amount of rain, and the context!

Poppy lapping up a puddle
Poppy lapping up a puddle

Regardless of the timing of rain within the fruit season, it’s important to make sure your soil can act as a big “water storage tank” when it rains. As well as building really healthy soil (which is good for both water storage and drainage in your soil), techniques like swales and keyline (covered in this short course) can make a huge difference to how well your soil will store rainfall.