Archive for category Soil Fertility
Tomatoes are one of my favourite foods so I grow as many as I can fit in my garden and choose varieties for their flavour, use and season and I make sure of a good crop by really taking care of them. As with most plants if you give them a good start and the best growing conditions you will be rewarded with better crops and stronger plants that need less care in the long run.
Choosing Tomato varieties
My favourite eating tomato is still Noir de Crimee, a black Russian heirloom; odd shape, odd colour but fantastic taste. Cherry tomatoes are a must for me as they are great to graze on while pottering around the garden. Next I make sure I have plenty of tomatoes for preserving, some varieties being better than others, the best I’ve tried so far are San Marzano and Roma for paste and sauces see the page on best preserving tomatoes. The other thing to consider is the length of the season. Some tomatoes bear fruit more quickly than others and are normally described by the number of days from planting out to first fruit ripening i.e. Early 55-70 days, Mid-Season 70-85 days and Late beyond 85 days. Next is variety of flavour and colour which makes for wonderful mixed tomato salads so it is nice to grow a few mild white tomatoes, acidic green ones and puunchy orange ones.
The first thing about tomatoes is that they need plenty of nutrients to produce all those lovely fruits, but the nutrients need to be added as they grow, if you put too much in at the beginning they are more likely to have too much leaf growth at the expense of fruit.
Tomatoes need a constant medium level of moisture. Too dry, too wet or too much fluctuation often causes blossom end rot resulting in unusable tom
atoes. Prepare the soil where the tomatoes are to be grown either by preparing planting holes, troughs or the entire bed. I prefer to prepare troughs as this helps to direct the most nutrients and moisture to the roots and it makes it easier to water when needed. Dig a long ditch 2 spades deep and 1 spade wide. Put a layer of chopped comfrey leaves on the bottom and half fill with a mixture of well rotten compost and manure 9 parts compost to one part manure and water heavily to fill the trough.
Plant the tomatoes in the bottom of the trough, as deep as you can, right up to the first set of true leaves, remove the remaining baby leaves. Roots will grow from th
e stalks giving the plant more stability and ability to draw more moisture and nutrients from the soil cover with dry soil but leave sides to the trough. This will help protect the young plants from wind and help direct water to the plants.
Spacing and Staking
Tomatoes need a fare bit of space as they don’t like to be crowded. It depends on how you plan to grow the tomatoes as to what distance apart they should by anything from 40-75cm apart works. I normally set out at around 50cm apart and grow them as cordons, that is straight up a pole with one main stem or sometimes two depending on how vigorous the variety. Cordon tomatoes need to be staked, I use 2 meter metal, chestnut, or cane poles with a cross brace on windy sites. Tie in the plants as they grow so that the tops are firmly but gently attached to the poles.
Once the tomatoes are in place add a top dressing of organic soil enhancer such as seaweed meal or well rotted manure. The dressing will gradually be brought down into the soil by water and the soluble nutrients can then be drawn up by the plant as it grows.
Applying a mulch, a top cover, over the ground around the tomatoes will help protect the soil and plants and conserve the moisture level in the soil. For more details on mulching read Using Mulches
Intermediate tomatoes have a habit of growing into bushes which produce a lot of leaf and plant growth but less fruit. In order to concentrate the plants energy on the fruit it helps to pinch out the side shoots. That is the little sprouts that form between the main stems and a leaf branch. Pinch these out with your fingers when they are less than 12cm. If you have missed a few and they have got bigger cut them off with clippers or a knife so as not to tear the plant.
Tomatoes benefit from a liquid feed, applied every 2 weeks, once the fruit start to form. You can buy ready made preparations but why not make you own. For more details on liquid feeds read Making Organic Liquid Fertilisers
Russian Comfrey is one of the most versatile plants for the organic kitchen gardener as it is a fantastic natural source of potash-rich organic material and liquid feed. It’s many uses include; compost activator, liquid feed, potting mix, soil enhancer, mulch and bee attractant.
The real value of comfrey lies in its composition. The roots bring up potassium, phosphate and other minerals from deep in the ground to the leaves which are also high in nitrogen. Comfrey has 2-3 times more potassium than animal manure, which makes it especially good for the production of flowers, fruits and seeds.
Beware Russian Comfrey (Symphytum x uplandicum) is quite a different plant from Wild Comfrey. (Symphytum asperum). Russian Comfrey is a hybrid and is sterile so does not freely seed. Wild Comfrey seeds madly and can be a real nuisance, we had some growing in our garden in England and I could not get rid of it.
There are many ways of growing vegetables; in fields, beds, trenches, flooded areas, sunken beds, rows, vertically, square foot beds, grow bags boxes and pots, even in nutrient rich water.
In our area people generally rotivate their land each spring and plant the vegetable gardens out in rows like a mini version of field cultivation. I followed the local way in our first year here but found that our light stony soil was non the better for it; the nutrients and humus I added were just getting washed away during the torrential rains in autumn. So now I prefer a raised bed system; for our sloping growing land with soil that is light, shallow and stony over rock, a raised bed system is what works for us.
Benefits of using a raised bed system
- Soil depth is increased as mulches are applied each year
- Soil does not get compacted because it is not being walked on
- Soil is kept aerated and weeded by hoeing the top few inches
- Soil structure is improved by keeping it undisturbed (digging light soil just turns it to dust).
- Soil fertility can be improved as and where needed and in rotation
- Water is conserved by tailoring irrigation to the needs of the crops in each bed
- Planning and rotating the growing area is easier because beds are fixed
- Easier to provide specific soil requirements for plants with special needs.
- On a sloping site a raised bed can level the growing area
- Work is reduced by digging soil only once and thereafter leaving it alone
- Taller edges can be made to protect and support some plants
- It just looks tidy! when i go down to the kitchen gardens it is easy to walk between the beds and harvest what i need.
For us the benefits of a raised bed system outweigh the downsides. Raised beds are less suitable to the light sandy soil and dry conditions we have here, as raised beds have a tendency to dry out faster. However, the fact that the beds won’t be dug over again helps to maintain the soils structure and by top dressing with muck and compost twice a season and mulching in summer we are able to increase the fertility and water retention of the soil making it less prone to drying out in the long term. The bed edges also help to protect the top soil from being whipped away by the long, dry summer winds.
Edging the beds
I did try to just visually mark the bed boundaries because I wanted to be able to change the layout each year but I found that the top dressings and nutrients got washed away in the heavy rains. The higher the planting areas got and the lower the paths got the more got washed away and the growing areas became smaller in time. So I ended up edging the beds.
Ours are not the smartest looking beds, most are edged with whatever i can get my hands on; old planks, the round end bits of trees left over from milling, flat stones, I even tried making some woven edges – far too pretty for my garden, rather pointless and they only lasted a single season but they did look cute (see pic above). I have learned to just make the best use of what I have around without causing myself extra work.
Adapting growing methods to climate and land
We live in a mountainous area which has unfortunately been given over to the mono-culture of pine trees but it would have been covered in a mixed deciduous forest with shrub and low growing plants. This year I plan to start fencing off some new areas of land to try growing edibles in a more natural forest-like way. No fixed beds just a layering of planting that will mirror the way plants grow in nature with trees, bushes, climbers, perennials and annuals (if they self seed) all taking their place. I want to see for myself which is more productive and uses the least water; the permaculture way as advocated by Bill Mollison or the fixed bed intensive growing the way i do it now. Gardening is about adapting and being open to find out what works for each piece of land and climate see Kate’s picture of some clever irrigated sunken vegetable beds in India @ Hills and Plain.
Revised and adapted from my original post 26/3/2007
Mulching is a simple technique of covering bare soil to; protect it from erosion and compression and to suppress weeds and retain moisture. Soil can be mulched with hard materials such as plastics or stone but better still are materials that are degradable because they also add nutrients, humus and improve the condition of the soil over time.
Best materials to mulch with
- Garden compost with a minimum depth of 2.5cm
- Wilted comfrey leaves excellent around solanum family and soft fruit. Layer 2 -3 leaves deep
- Dried grass clippings 5cm deep
- Weed free straw 10-15cm (6”) which settles to less
- Bracken chopped spread in layers 4-5 leaves deep
- Half rotted compost this is bulkier and good around large plants and to cover larger areas.
- Leaf mould, excellent soil enhancer brought down into the soil by worms
- Well rotted manure nutrient rich apply to greedy plants such as fruiting crops and corn.
Pine needles are not suitable for all crops but strawberries love a thick mulch of pine needles. Wild strawberries are forest plants and can often be found around pine forests so this is a good way to replicate their natural environment it also keeps the fruit clean and off the soil and deters slugs.
When to mulch
The golden rule of mulching is to mulch when the soil is in perfect condition, in most cases when the soil is warm and moist. Mulching will maintain the condition of the soil so do not mulch if the soil is too dry or cold and wet, mulch when the soil is warm after rains or the ground has been watered.
Mulch when planting out or soon afterwards. Mulches can also be applied:
Autumn mulch overwintering crops: celeriac, leeks, parsnip, kale, winter radishes to keep soil warm, preserve soil structure and reduce ground frost making it easier to lift roots in frosty weather.
Early spring mulch lightly with garden compost after digging unless the soil is very wet. It will keep the soil in good condition ready for sowing and planting later.
Late spring summer mulch between rows after seedlings have germinated and between growing crops such as peas, beans, onions and carrots.
Summer mulch summer fruiting crops with a thick layer of straw to keep moisture down in the soil suitable for tomatoes, aubergines, peppers, courgettes, also good for cucurbits and other sprawling plants to keep their fruit clean and of good quality.