We’re just a week or two away from the first decent crops. In the small polytunnel, the broad beans, beetroot, kohlrabi, new season spinach, chard and kale are just about ready. Despite a bit of frost damage a few weeks back, the early potatoes have recovered well and should be ready in two weeks. I earthed up the later-sown main crop spuds this week. Garlic and onions are doing well, and the elephant garlic has produced scapes in the last week.

These can be snapped off and chopped up in to stir-fries and the like – they are a delicacy and absolutely delicious.

The big tunnel is filling up nicely – all the tomato plants (all 90 of them!) are in and doing well. I got some new seep hose, which extends all the way up and down the three beds – this should make watering a little easier this year. This week past I planted out the peppers and the climbing French beans.

I sow the beans the same way as the tomatoes and cucumbers, with a string planted underneath the plants, which is then tied to a cross bar at the top of the tunnel. The beans will quickly reach 10m high (though you can stop them before that by pinching off the growing tip if you wish).

I start French beans in modules for later transplanting as it gets them a head start on the slugs, and then I plant two seedlings at the base of each string (about 30cm apart). From two 3m rows of plants we will have loads of beans – enough to keep us going for the summer and autumn, and plenty for the freezer.

Cucumbers are only a week or two away from being ready to eat, and I’ve more plants coming on in the potting shed. This year, we’re trying cucamelons as well – these produce tiny 2-3cm long fruits that look like mini watermelons but taste more like cucumbers. it will be interesting to see how they fare.

Cucumbers and tomatoes have slightly different watering regimes, which can be a challenge when you have them growing in the one place. The cucumbers like it steamy, which means watering the plants from overhead to create a humid atmosphere.

Tomatoes on the other hand, benefit from a drier atmosphere and need water deep to their roots (see below).

From a sowing perspective we are moving on to the quick growers now.

We’re not quite at last chance stage for sowing, but June is probably the peak of it for this year. In the potting shed I was busy this week sowing squash (delicata, crown prince, uchiki kuri and butternut) – I have space for about 40 plants in a piece of unused ground beside the big tunnel and I really think you can never have too many of them, since they store so well. Any excess will be snapped up by the kitchen at GROW HQ.

In the potting shed I also sowed sweetcorn, fennel, runner beans, basil, parsley, coriander; out in the veg patch I planted out celery, courgette and summer squash; covered down the carrots with bionet (to keep out the carrot root fly); direct sowed another 2m of peas and kept on top of the weeding (particularly in the parsnip and carrot beds). Phew.

The basics – watering tomato plants

At this stage of their development, it’s vital to make sure your tomato plants are getting enough water. Because they are a deep-rooting plant, it’s not effective to spray water at the soil (or worse, at the plant itself, which would encourage blight). The key is to get water right down to the roots.

For a smaller number of plants, the best way to do this is by sinking a container in to the soil beside the plant and water in to that.

Use upturned 2l milk cartons with the bottoms cut off them and the spout facing down. Watering becomes a job of simply filling the container, confident in the knowledge that the plant is getting 2l of water where it needs it most. For a larger number of plants a seep hose is a good alternative, which soaks the soil very effectively.

Watering “at depth” like this also means the plant is less vulnerable to drying out in very warm polytunnel days, because the water won’t evaporate as easily as it would from the surface of the soil.

Water the tomato plants in this way every other day – as a rough guide you want to give the plants about 10-12 litres of water per week.

Michael Kelly is an author, broadcaster and founder of GIY.

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