Water and Weed

With this weather, the main thing is water. Check often, and water enough that the soil is damp below the surface.  It's okay if just the very surface is dry. With containers, you probably have to water every day right now. The ground probably only needs to be watered every other day. You will need to water less if the spot is less exposed, or if you have covered the soil (see the note about mulching below) - or if the weather cools down a lot, or it actually rains, both of which are possibilities in the forecast.

When you water, water twice. Ideally your plants are in a bit of a shallow bowl or trough in the soil, so that when you pour, you can make a little pool. Then when the pool has drained, repeat again. The pool of water creates some pressure to push the water down deeper into the soil. That zone is more protected, and roots will grow into that zone and have access to a more stable moisture level. Even shallow-rooted plant types will grow at least 6 inches down. (Deep rooted plants grow much further, sometimes metres down.)

Also, if your plants are large enough (at least 4 inches tall), you can "mulch", which nowadays means any way of covering the soil. In hot weather you want something that will protect the soil from direct heat of the sun, and so reduce moisture loss by evaporation. Straw and compost are both good hot weather mulches. Spread them out so there's an insulating layer over the soil.

One drawback of mulches is that they protect slugs and snails, so if you know you have a lot of those, you might want to wait until plants are larger (at which point the slugs and snails don't cause much harm).

Although this drought means more watering, it does help control the weeds, which certainly also need water. Still, you probably have weeds to pull out now too, unless you are growing in containers, in which case possibly no weeds have found your plot yet.

Planting Time for Warm Weather Crops

The weather is perfect to plant warm weather crops. On our shortlist, that's beans, tomatoes, basil, and nasturtiums.

Beans

If you are planting beans, it's much, much better to soak beans overnight or even for 24 hours before you plant them, since they will germinate much faster that way. (If you are really, really in a rush, I think you can just plant them without soaking, but make sure to keep the soil quite wet, or they won't sprout for a long time.)

Beans are simple to plant. Check out the spring greens planting instructions. On the seed package, it will say how deep to plant your variety of beans, but they usually should be 1 or 2 centimeters deep, depending on the size of the bean.


The others warm-weather vegetables on this list: tomatoes, basil, and nasturtiums, are usually planted as seedlings rather than as seed. In principal, they can be grown from seed in the garden now, too. If you do that, you should know that they may take a while to sprout, and also they are quite slow growing at first and often get eaten by slugs, snails, or other critters when they are tiny. So you should plant a few extra seeds in place and then thin out later. The harvest will be later. For tomatoes, in particular you're probably much better off with seedlings.

Transplanting Seedlings

Dig a hole that fits the little pot your seedling is in, but is deeper.

Add some compost (if you didn't already prepare the soil with compost this year), and try to loosen and mix the dirt that will be surrounding and underneath your seedling. This makes it easier for the seedling to grow its roots, which will be quite deep and wide in most cases.

Carefully remove the seedling from the pot, with as little stress on any part of the plant as you can manage. It often helps to tear the thin plastic of a nursery pot away from the earth and roots in the pot. You are trying to disturb its roots as little as possible, since the roots are very fragile. The actual root hairs that absorb water are microscopic. The more you damage those, the less water and nutrients the seedling will get after planting, until it can regrow them.

Stressing the seedling and its roots as little as possible, lower the roots into the hole with one hand, and use the other to fill in earth beneath it and around it. Press down gently to firm up the earth it's now planted in.

Ideally, the plant ends up in a very slight depression, making it easy to water. Water by filling the depression with a cup or so of water, so you can see that as the water soaks in, the earth surrounding the seedling is well wetted, but not soupy.

For most plants, you should take care when transplanting not to add any extra earth around the stem of the seedling, which might rot it. Tomatoes are an exception to this. For tomatoes, deliberately plant them deeper when you transplant them, as deep as the first set of leaves. They will grow additional roots from the submerged part of the stem, making for a stronger, healthier tomato plant later.

You should make sure that the transplanted seedlings have slightly moist soil at all times for at least a few days, while they regenerate their roots. Looking at the weather forecast, that probably means you will need to water them every few days for a while. Check by poking beneath the surface. The surface may look dry, but if it's damp underneath that's okay. If it's almost dry underneath, you should water more.

As the plant gets growing, you should stop watering so frequently. The plant will grow a stronger root system if you water deeply every week or so (unless it's rained and you don't need to water). Watering deeply means you keep supplying water (pour water into the depression or trench around the plants a few times) until it's seeped well down into the soil.