Prepare Clay Soil for Spring Planting

Prepare Clay Soil for Spring Planting

Clay soils can be heavy and difficult, but if you persevere they can be very fertile and productive. Ideally your soil will contain at least 20% clay, but no more than 35% (or you can have problems). While clay soils hold on to nutrients well, you may have to adjust the pH of the soil to make the nutrients available.

The downside of clay soil is that roots have a hard time penetrating it because the pores are so small and the particles so densely packed. Additionally, clay soils hold a lot of water (up to eight times as much as a sandy one) and are slow to dry out. This is an advantage in times of drought, but in wet climates it means they get waterlogged easily. Wet clay soils tend to be cold and slow to warm up in spring. It’s no wonder that many plants don’t over-winter well in clay soils.

Use the tips below to turn your clay soil into an environment your plants and other beneficial organisms will love.

Tips for working with clay

•    Limit cultivation to times when soil is not too dry or wet. If you work with dry clay soil it will be so hard it is almost impossible to dig and may crack into large chunks that crumble to dust. When this dust gets wet it sets rock hard, almost like plaster. Cultivation of wet clay is even worse. Wet a clay soil compacts very easily when you put any pressure on it, creating a sticky mass that is also hard to penetrate.
•    Roughly dig the soil in autumn, when it’s relatively dry, and leave it over the winter for frost to break down the large clumps.
•    Add well-decomposed organic matter to help particles cluster together and form larger aggregates. This will improve drainage and aeration.
•    Use green manures to improve structure.
•    Double dig to incorporate organic matter and calcium.
•    Use raised beds to improve aeration and prevent future compaction. Build them high to help them drain and warm up.
•    Slope the sight slightly so the soil can drain more quickly.
•    Never allow the soil to get so dry that is cracks. These cracks increase evaporation and make the soil hard to re-wet because water simply drains away down the cracks. If it does dry out, cultivate the soil surface.
•    You can improve clay soil’s structure by adding a  mix of 80% gypsum and 20% dolomitic lime. Use an ounce of this mix per square foot of soil in spring and again in fall. This may be repeated for a second year, while also adding as much organic matter as possible.
•    Adding calcium may be useful to improve soil structure temporarily, until you can get sufficient organic matter and soil life into the soil. But this only works if the soil is low in calcium.

The Winter Vegetable Garden

The Winter Vegetable Garden

As the days grow shorter and the temperatures drop, many gardeners move indoors for the winter. But for those of us who live in a mild climate where we can grow late autumn and winter crops, we can keep right on growing as long as we pick the right crops, get them in the ground early enough and provide them with the proper protection.

Crop Selection

Some cool weather crops are much better suited to growing in autumn than in spring. Often by the time it’s warm enough for plants to mature in spring, longer days will cause short-day crops (spinach and oriental cabbage) to bolt. The warm temperatures adversely affect their flavor as well. If you plant these crops in late summer, they’ll grow quickly to start and then mature more slowly in the shorter colder days that follow.

For cold weather growing, stick to the tried and true hardy crops:

•    Broccoli
•    Brussels Sprouts
•    Cabbage
•    Carrot
•    Cauliflower
•    Chard
•    Citrust
•    Cornsalad
•    Horseradish
•    Kale
•    Jerusalem Artichoke
•    Leek
•    Mustard Greens
•    Parsnip
•    Turnips

It is important to use the right crop variety at this time of year, as hardiness varies considerably within a crop.

When to Plant

Fall and mild winter crops commonly take longer to mature because the sun is weaker and the days are shorter. To determine the right time to plant a fall crop, figure out the number of days it takes for it to reach maturation (adding extra days to allow for slower growth in autumn). Then determine the day you want them to mature (in areas with frost, this is normally just before the weather turns too cold for good growth). Subtract the number of growing days from the maturation date and you have the sowing date.

It’s a good idea to plant a few successions at this time to make sure you get at least one crop before the frosts and possibly more if the frost is later than expected. If you rarely have frosts, you may be able to continue growing these crops through the winter.

Where to Plant

The beds for winter crops should receive all of the sunlight they can get, so make sure they won’t be shaded. A south-facing slope is the best choice as it gets extra heat from the sun. You might shape your shape winter beds so they tilt slightly to the south to give them a little extra solar gain.

The beds should be well protected from cold winds. Don’t plant the winter garden in a low-lying area, as it might be a frost pocket and much colder than a more elevated slope. The soil should also be well drained, as dampness is often as great as enemy of winter plants as cold is (much of the value of cloches and cold frames is due to their protecting plants from moisture).

Season Extension

The simplest season extending technique is to protect the tender crops from the first occasional autumn frosts. If protected, the plants can sit in the cold garden in an edible state for weeks before having to be harvested. The hardiest autumn/winter crops will continue bearing until temperatures drop down into the 20’s.

The first frost may be followed by several weeks of good growing weather before the next one, so the simple act of covering your plants for a night or two may reward you with several more weeks of harvests.

A quick freeze will do a lot more damage to plants than a gradual decline in temperature (which gradually hardens them off). Happily you can get advance warning of an oncoming frost and act to protect your plants. Almost anything will give protection from a light frost:

•    cloches
•    cold frames
•    old blankets
•    row covers
•    plastic sheeting
•    hay or straw mulch

Cold frames and cloches can even protect plants from more severe frosts. Tall plants such as tomatoes can be unstaked and laid down on the ground for easier protection.

If your unprotected plants are hit by an unexpected frost you may be able to revive them by washing the frost off with a spray of water. This must be done before the sun hits them and thaws them out too quickly. You can also follow the example of commercial citrus farmers and leave a slow sprinkler going all night (don’t turn it off until all ice has melted). But this wastes a lot of water.

You should protect the tender crops for as long as there is good growth in the daytime. It isn’t worth protecting them once the days get cold, as they won’t thrive. It is better to replace them with hardy crops. Or maybe you do want to take a break for a month or two and hibernate. If you’ve been diligent and canned, dried or frozen some of your earlier harvests, you can enjoy the fruits of your own garden until you’re ready to start preparing again for the spring.