Head gardener Benjamin Pope and vegetable gardener and cook Aaron Bertelsen are here to make sure your garden looks great all year round. Don't miss our suggestions of the best flowers in June, what gardens to visit and the gardening jobs for the month.
What to plant in June
What to sow and plant - Benjamin Pope
Although the spring rush of sowing and planting has peaked, there are still things to keep busy with. I like to sow biennials and perennials now or next month, so that they reach a good size and can be planted out before winter arrives. I can’t resist the elegant spires of Digitalis in all its forms, from charming biennials, such as Digitalis purpurea ‘Sutton’s Apricot’, to the perennial species, including Digitalis lutea and Digitalis parviflora.
Delicate Verbascum blattaria f. albiflorum is something I always like to have, informally dotting it around the edges of borders and paths.
For cutting or bedding out, it is worth sowing sweet Williams (Dianthus barbatus) and my preferred selections would be the vibrant ‘Oeschberg’, sumptuously dark ‘Sooty’, and the bi-colour ‘Purple Crown’ and ‘Sweet Pink Magic’.
In the vegetable patch there may be some succession sowing of beetroots and carrots or salad leaves and herbs, especially if your existing crops are harvesting now or beginning to bolt.
Any last-minute planting out to fill the odd gap can also be done now and I find using quick-growing annuals such as Bupleurum rotundifolium, calendula and tagetes very successful, although it’s worth remembering these plants will need additional watering to help them establish, especially if the weather is hot and dry.
What to sow and plant out - Aaron Bertselsen
A lot of people seem to look down on perpetual spinach, considering it less refined than the regular kind, but for me it is a must-have crop. It’s easy to grow, very productive, does not easily run to seed and given a mild winter will keep cropping right through to the following spring. Then, when it finally does run to seed you can pull up the whole plant and eat the stems, any remaining leaves and even the seedheads – delicious steamed as a side dish. It is such a robust, good value plant. Really, the only thing you need to remember is to keep picking often to encourage more growth. That way you will always be eating young tender leaves.
I sow the seeds in a 10cm pot under glass or on the windowsill. Once the seedlings have their true leaves, you can plant them out into the ground or a pot. Leave a trowel’s length between the plants in the open ground, less in a pot. Perpetual spinach also does well if sown direct, although you will need to be on your guard against slugs on the look out for something young and fresh. Once the seedlings reach a decent size, thin them out and use the thinnings raw in a salad.
What to plant out
By now your tomato plants should be ready to plant out. I am guided less by the size of the plant than by the temperature. Tomatoes need plenty of time to ripen, so I get them into the ground as soon as the temperature consistently stays above 7°C at night. Most of the problems that affect tomatoes are soil-borne. In the garden, put them in a new patch of ground every year, aiming for a five- or six-year rotation. In containers, use fresh compost every year. Get your stakes in the ground or pot before you plant out, and make sure they are sturdy enough to hold what will eventually be a 1m-plus plant with lots of fruit. Water in well and keep watering regularly, to stop fruits from splitting as they develop.
As the plants grow, tie the main stem to the stake at intervals, using twine. After a month or so, give them a good feed with liquid seaweed or tomato food. Be careful when you water to avoid splashing soil on to the leaves. Removing the lower leaves will help with this, as will sowing or planting something else around the base of the plants. I use French marigolds, as their scent also acts as a deterrent for aphids.
