Attracting beneficial insects

Attracting beneficial insects

Beneficial predatory insects are an important element of an organic pest control strategy. Unless you have a serious problems, if they are living in your garden they will help to control pests without you having to do anything. While some insects, like ladybugs, can be purchased and released in your garden, you don’t really have to work at attracting beneficial insects, just provide the simple things they need and they will come.

Food
One of their requirements is a source of food, which mainly means lots of small nectar and pollen producing flowers (many beneficial insects are very small and have difficulty feeding from larger flowers). Plants of the carrot (Apiaceae), daisy (Asteraceae) and mint (Lamiaceae) families are all particularly good. This is why the herb garden is always alive with insects and is another good reason for planting many of these plants. Many weeds are good sources of food too. Highly bred garden cultivars aren’t very useful because they are often sterile and don’t produce much nectar or pollen.

Habitat
The other important need is for a diversity of undisturbed habitat, which gives them a place of refuge from predators and a suitable place to survive the winter (they won’t survive in the ever changing annual vegetable garden, which is often bare in winter). This can be a simple border, with a diversity of perennials and shrubs to give them a place to live.

Keep your berries healthy all summer

Keep your berries healthy all summer

Berry plants tend to be fairly low maintenance plants, put them in the right place, keep them watered and they will grow stronger, bigger and more productive every year (until they threaten to fill your whole garden and you have to start restricting them). Even so, there are a couple of things you can do to help your plants and increase the harvest for years to come.

In most places the most important thing you need to do for your berry plants is protect them from birds. Birds love berries just as much as you do (after all, berries were created to be eaten by birds as a way of transporting the seed). If given the opportunity they will strip the bushes of every edible fruit. You could try various ways to scare them away — shiny tape, inflatable predators, scarecrows — but birds will soon figure out that these aren’t a problem, so they don’t usually work for long. The only foolproof way to foil the birds is by carefully covering the plants with netting (this has to be done thoroughly because they will look for any openings). Applying and removing netting is a real pain because it snags on everything it touches (be careful it doesn’t tear) and is one of the few garden jobs I really dislike. If you have to do this every year, you might think about putting your berries inside a permanent fruit cage (the simplest of these is made from PVC pipe).

The other important maintenance activity is removing old stems to encourage vigorous new fruiting growth. Blackberry and raspberry canes usually die after their second year and can create a dense thicket if not removed (these can be removed after they have finished fruiting). Blueberries and currants fruit more vigorously on younger wood, so every year some older ones are removed to encourage new growth.

To keep the plants growing as vigorously as possible, you also need to keep them well watered. Keep the soil moist, but not wet. If the plants are bearing heavily then some fertilization may also be needed to keep them producing well. The best way to do this is to apply some mulch, which will also keep down weeds and conserve moisture. Just be sure to use an acidic mulch such as pine needles for blueberries, since they need a bit more acid.

Gardening in extreme heat

Gardening in extreme heat

This year has brought record high temperatures to much of the country (again, but don’t worry, Exxon says this has nothing to do with global warming), so I wanted to say something about keeping your vegetables garden happy when the mercury soars.

Pick the right plants
High temperatures don’t just make plants uncomfortable, they can actually stop them growing and seriously affect productivity. When it gets too hot we can simply stay in the shade, or go into the house, but plants are stuck in the full sun and have to deal with it. Your choice of variety is also significant as some are more heat tolerant than others. Look for those that were developed for the tropics, desert or southern states, as many of these plants have developed several mechanisms for coping with heat stress and these are the most reliable plants to grow in hot weather. They include cowpea, okra, melon, pepper, tomato, sweet potato, lima bean, watermelon, and amaranth.

But even heat-tolerant fruiting crops (beans, tomato, eggplant, pepper, okra) can have problems when it gets much above 90 degrees Fahrenheit because flowers may not pollinate and will drop instead of setting fruit (plant breeders are working on heat resistant varieties that don’t do this).

Water them well
Just as it is essential for humans to drink plenty of water during hot weather, so it is with plants. Your first priority should be ensuring they get enough water, as this will help them to keep growing and producing (without it they are toast). The best way to water in hot weather is with a drip system, such as in-line drip irrigation tubing or soaker hose, which allows the water to quickly soak in to the ground. Overhead sprinklers aren’t as good because a lot of the water will often simply evaporate in the heat. If you must use sprinklers then avoid watering in the middle of the day, do it in the cool of early morning or early evening (early enough that plants don’t stay wet all night). Water is especially critical when plants are sizing up fruit and blossom end rot is often a problem if watering is irregular.

Mulch to keep them cool
Bare soil dries out quickly when exposed to the fierce heat of the sun, so it is also important to keep it covered as much as possible (there is no point in supplying water and then watching much of it evaporate). The most convenient mulch is a 2 to 4” layer of straw, which is readily available at feed stores. Mulch also keeps the soil cooler by shading it from the heat of the sun (plants can cope much better if their roots are cool). It also prevents the growth of competing annual weeds.

Give them some shade
In extremely hot conditions strong sunlight can be a problem because it raises temperatures even further. In such situations plants may benefit from some kind of shade during the hottest part of the day. This could be provided by shade cloth over hoops, or some kind of wooden framework covered with trellis, or even sticks (to create dappled shade). You can also create shade by planting tall plants such as sunflower or corn, but of course these require water too.

Help them recover quickly
Many plants (especially those with big leaves) wilt naturally in the heat of the day to reduce moisture loss, but they recover quickly when it cools down. If plants don’t recover quickly when the temperature drops, they are severely stressed and need water. Prolonged water stress is easily identifiable because leaves (and sometimes fruit) become bleached or scorched and growth is slower.

Take care of the gardener
It is also important to think about yourself in hot weather. Drink plenty of water and keep out of the garden during the hottest part of the day (also wear a hat). If you are an early riser the best time to be in the garden is when the sun first comes up, it is so beautiful and peaceful. I tend to come to life in the evening and get most of my work done in the couple of hours before the sun sets.

How to mulch

How to mulch

I consider mulch to be an indispensable part of the summer vegetable garden.

  • reduces evaporation of water from the soil
  • prevents weeds (many weeds need bare soil)
  • supplies nutrients to the soil (when it breaks down)
  • protects the soil from damage by sun and air
  • reduces disease (by preventing soil splashing on leaves)

 

If a genetically engineered commercial product did as much, it would be patented, hailed as a miracle of science, promoted in all of the garden magazines and sold for a hefty price. Yet mulch does all of these things and more and costs next to nothing (or nothing).

The best all around material for mulching the annual vegetable garden is straw (avoid the similar looking hay at all costs, as it is full of weed seeds and can turn your soil into a weedy nightmare). Straw comes neatly compacted into a convenient (if rather heavy) bale, is clean and easy to use and looks quite attractive on the bed. If you are growing transplants, you spread a 2 to 3 inch layer around the newly planted plants (it will settle as you water). If you are direct sowing you have to wait until the seeds have germinated and the plants are a few inches high before you can apply it.

If you don’t have access to straw, you can use grass clippings or chopped tree leaves (run these over with a lawnmower to chop them, or put them in a metal bin with a string trimmer). Compost can be used as mulch too, if you have enough of it. You can also buy the hulls of cocoa bean, cottonseed and buckwheat for use as mulch, but they are expensive when compared to straw.

The only time I don’t recommend mulch if you have lots of slugs (it provides the perfect hiding places for them) or when you want the soil to warm up rapidly (it insulates it from the warming rays of the sun). Otherwise, it’s probably the most important thing you can do for your garden.

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.