Green vegetable bug and Crop rotation

I last wrote with great delight about our magnificent early tomatoes. Sadly pride comes before a fall and that same crop has suffered so badly from Green vegetable bug damage that I have turned the water off!

Green vegetable bug is a sap sucking insect. They feed on a number of plants and in the great reference book “What Garden pest or disease is that” Judy McMaugh these include pumpkins, capsicums, potatoes, spinach, oranges, peas, passionfruit, beans and tomatoes (plus other garden plants). Yikes – that is a decent list for a little green bug.

vegetable-bug

Various stages of green vegetable bug maturity

This beautiful image painted by E.H Zech for the NSW Department of Agriculture  shows what the bug and eggs look like at various stages of maturity.

So what am I going to do? Well this is a bug that doesn’t have a a quick fix solution and according to DPI literature is a difficult bug to control. Fortunately it appears efforts have been made to find biological controls but I am not seeing these in our crop.  In fact, I have the bug nicely trapped under the fruit fly netting at present.  So, I will firstly aim to trap them in there and not allow escapes to feed on other crops not netted. The life cycle of egg to adult is around 8 weeks – once our tomatoes have died under the net I will look at knocking the crop to the ground and solarising the whole lot under black plastic.  The aim will be to kill off any maturing or adult bugs and existing eggs.  I will keep you posted.

What I should have done much earlier in the season was put on the fruit fly netting.  I delayed the netting as our fruit fly population has been managed well in recent years.  Not so the Green Veg bug!

This leads nicely into the topic of crop rotation.  Whenever Seed Savers run workshops or I have presented at other workshops crop rotation regularly comes up as an area many would like to know more about.  The above insect problem gives a great example of one of the number of reasons why not planting the same crop or plant family in that location each season is important .  I say season because in our southern NSW climate we can grow crops (seasonally appropriate) in the same ground year round.  So after the tomatoes I will grow a green manure crop (probably grass family – over the winter) that is not favoured by green vegetable bug and then a summer crop also not favoured by this bug – say Asian greens and herbs or a root crop of beetroot, carrots and onions.

Generally the main aim of crop rotation is to reduce build of pests and diseases and to allow the building of great soil life to benefit subsequent crops.

As a starting point get to know your plant families that most of the vegetable belong to. Also get to know the growing needs for of each of these groups. This information can be readily found in books such as the Seed Savers Manual.  A couple of the main families are:

Solanaceae Family (hungry crops for nutrients)– tomatoes, capsicums, eggplants, potatoes

Brassiacaceae Family(lots of nitrogen) – broccoli, Brussels sprouts, kale, cabbage, radish, mustards, rocket

Fabaceae (can proved valuable nitrogen)– beans, peas

Cucurbitaceae (hungry feeders and need lots of water)– cucumber, pumpkins, squash, melons

Apidaceae(don’t like much nitrogen and like milder conditions) – carrots, celery, parsley

Liliaceae – onions, leek, garlic

Asteraceae – lettuce, artichoke, dandelion.

You can start to see the potential for a pattern to emerge for planting different crops before or after each other.  As a general guide you may try something like this;

ROOT CROP (carrots, parsnip & beetroot)

LEGUME CROP (peas, beans)

LEAFY CROP (broccoli, kale, cauliflower) add some well decomposed compost then

FRUITING CROP of tomatoes.

You could simply group plants together by the characteristic of how they group eg all root crops.  I have been moving away from this as I refine what I grow. For example, I now have all the tomatoes, potatoes, capsicums ect growing together as they grow in the same season and all tend have the same needs.  So far I am happy with this plan.

Crop rotation does require planning and a bit of shuffling around with what can go where and when.  I enjoy this planning and thinking but can appreciate the headache it can give others.  In this case I have suggested that don’t stress about crop rotations until you see some evidence of something not going well in your garden. Alternatively – when I started down this path I simply aimed to just make sure my tomatoes didn’t grow in the same spot season after season.  This is still the group of plants from which I begin planning rations for summer planting.

Great detailed references for rotating crops can be found in books such as previously mentioned “The NEW Organic grower” by Elliot Coleman, “The Market Gardener” by Jean Martin Fortier and many other organic gardening books and magazines.

My main advice is start with learning about the plant families and the plant needs in those groups.  This will help you establish your own planning, planting, green manure cropping and adding compost plan to suit your garden and your space.

Tomatoes and successful experimenting with hot housing

I begin this blog with tomatoes and why I would like to write about our gardening experiences at Aquila..

With great excitement I have harvested well over 5 kilo of tomatoes already and have 5 large containers of cooked tomatoes frozen and squirrelled away in the freezer.  The aim is for 20 frozen containers and another 20 bottled tomatoes.  Despite the thrill I get each time I harvest and then consume food from our garden, this harvest is significant. It was an experiment that went wonderfully right! In late August we planted our tomato seedlings into the garden and set up temporary hothouses.  The system we used is base on one I read about in  Elliot Coleman’s book “The New Organic grower” Elliot travelled to France and studied the techniques used by French market gardeners.  So much of Elliot’s work and that of a Canadian market gardener Jean –Martin Fortier have shaped, inspired and changed how we have grown food these last 18months.

In-situ hot housing of tomato seedlings Aug 2014

In-situ hot housing of tomato seedlings Aug 2014

This system of hot housing is very simple. Before the tomatoes were planted the hoops of high tensile wire were stuck into the garden. Builders plastic was placed over the wire hoops.  The plastic is held down with long pieces of bailing twine, criss crossed over the plastic.  Warm soil and then warm air temperatures created by the hot house saw the tomatoes grow quickly and strongly.

It is this learning that I get excited about and part of the reason why I am keen to share it with other gardeners.  This simple low tech solution to getting tomatoes well before Christmas has lots of applications for other crops and extending seasons.  This system was new for me and maybe it might create a solution for you as well.  I hope so.

This blog also marks the beginning of a new aspect to gardening as the “A Year in Aquila garden” Seasonal guide to activities in your garden arrived from the printers and travelled to some gardeners for Christmas.  Self publishing and working on this project with friends Amy & Will has been incredible.  I learnt so much and look forward to seeing where the project goes in the future.

So I sign off this first entry with many wishes to all gardeners and growers of great food and hope the summer is kind and rewarding.  Cheerio Lou