The Island Garden
There are some gardeners who say that you should only put plants that grow above ground in the garden when the moon is shining and that root crops that grow below ground should be seeded when there is no moon. But they are not the norm; most gardeners wait for a nice sunny day and plant out. That's fun, for you, but not for your plants. Many plants have been grown in greenhouses or indoors and need to be hardened off before they should be planted in the garden. Even those purchased at garden centers and chain stores spend a lot of time undercover. So when you buy plants, check where they are growing. If they are outdoors, they can be plated right away; if they're sitting under cover you probably want to allow them a few days to get used to bright sunlight before planting out. A bright sunny day gets you sunburned on your back and butt as you bend over, but that is precisely the wrong time to be putting plants in the ground. If you put plants out on sunny days, they transpire - that is, water is given off from the leaves. If you've damaged the roots in any way or shaken a lot of dirt off the roots, the plant can't take up enough water to replace what has transpired and they wilt. The very best time to plant out is on an overcast day with a forecast of rain showers. You don't want heavy showers that will beat your plants into the ground, but misty moderate showers that will moisten your plants nicely. The overcast will slow their transpiration rate and the rain will moisten their roots. All you get is a wet back and wet butt.
Let's also talk a little bit about soils. Most people tromp around their garden like it's the High street, but stop and think for a minute. What grows in the High street? Nothing, because the ground is so compacted. (It's also blacktopped, but we'll assume that this High street is a muddy farm track and nothing grows where the wagon wheels roll.) Plants growing in compacted ground tend to be stunted because it takes far too much energy for their root systems to penetrate the hard ground. This means that they often are the first to succumb when a drought hits. So instead of tramping your garden flat when you put plants in the ground, try to stay to one side and reach into the growing bed or distribute the weight of your body by standing on a plank. Better yet, put the plank on bricks on either side of your garden bed and put no weight on the soil at all. The very worst time to walk on your garden is when the garden is moist on a dull overcast day with a threat of rain or just after a rain. Moisture in the soil allows it to compress easily and compaction is far higher, so not only do you need to plant out in the rain, but now you need to fly over your garden bed planting as you go! Just joking, of course.
In the vegetable garden
Look out for asparagus beetles. They're around and should be controlled or you may lose your plants. Similarly, look out for potato beetles and cabbage white caterpillars, although it's a bit early for caterpillars. Spray or dust your plants with BT, an organic pesticide. Hit onions and garlic with a second helping of fertilizer.
Plant out everything that you want to plant out now. Keep corn in clumps to make it easier to pollinate. While the corn is small you can grow lettuce and spinach between the corn stalks to save space. The greens will be harvested before the corn shades it. Seed beets, turnips and carrots in the dark phase of the moon next week (and you thought I was joking!) Put squash out and wrap the stems with tin foil to keep squash borers from drilling into stems. Don't know if it works, but it's worth a try. If nothing else they can admire themselves in the reflection from the tin foil.
Most bulbs have finished blooming by now and your perennials are coming along nicely. If you have gaps in the bulb garden now is the time to mark them for filling in this fall. Perennials may not be in flower yet, but they'll be here soon. You can dig and divide primulas about now. This will give them time to grow into their new area before they go dormant for the winter.
Containers Make sure you keep your con- tainers well watered in the hot sun. Small containers can dry out very rapidly. I find that even large citrus tree containers can dry in one day and need to be watered just before dusk after a hot day.
If you want to prune your Rhododendrons back, now is the time to do it, immediately after they've flowered. Don't prune fir trees yet, their candles are still growing. Mulch around shrubs to help reduce the stress of a dry summer.
Spray with summer oil (it's a lighter oil than dormant oil) to smother bugs as soon as flower blossoms have dropped.