Dahlias will delight with regular blooms

A beautiful dahlia

A beautiful dahlia

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What about growing some dahlias this summer?

They are one of the best flowers to grow if you like to pick flowers as they produce lots of blooms regularly. On most dahlia plants, there are always three flowers ready to cut.

From early July onwards they only last for four or five days in water. Once they are past their best and put into the compost heap it is possible to go out and cut another three blooms. This will continue until autumn.

Have a look at the picture on the front of the pack – the rounded pom types are in short supply this year – then check on the heights. Look for plump tubers. Tip the pack and you may see the signs of a yellowish green shoot arising out of the top. These buds or shoots indicate the tubers will grow.

Early blooms are encouraged if the tubers are potted into a suitable-sized pot which will accommodate the tuber. The pots are normally about four and a half inches in diameter and any potting compost is used to fill the pots. Bury the tuber but leave the tip about a quarter of an inch above compost level. If there are shoots, don’t cover them with compost. They must be in a light, frost-free place, keeping the compost only just moist.

If you like taking cuttings, the shoots can be used for this purpose once they are three inches long. Cut off the shoots required, leaving at least one on the tuber and then make a sharp cut below the lowest leaf joint (node) and insert the cuttings into a seed compost adding 50 per cent sand. The cuttings need to be kept warm, so a box covered with a sheet of glass makes a good propagator. Cover the glass with a sheet of newspaper to prevent scorching. They will root in three weeks.

They are then potted into small pots and grown on until the middle of May when they are hardened off and planted into the garden. Dahlias are tender, so cold winds can set them back and scorch the leaves. Frosts do even more damage, so hardening off means leaving them outdoors still in the pots in a protected place, such as a cold frame, for 10 days.

The soil into which the plants are to be grown is best dug over at this time of year and well rotted manure or compost can be incorporated. A balanced fertiliser such as blood, fish and bone meal can be used at a rate of four ounces per square yard and forked in over the dahlia border 10 days before planting.

Use stout canes to match the height of the plants. If the hawthorn where you live has finished flowering, then it’s safe to plant dahlias as long as the wind isn’t very cold.

Dahlias love a sunny spot which is well drained but they need lots of water in hot weather. They will grow in light shade too but the plants will be taller than indicated on the packet.

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