Big blooms can be achieved with some varieties of dahlia, Amateur Gardening’s Emilie Griffin explains how
STAKING AND TYING
Dahlia shoots can be very brittle at their base, meaning whole stems are easily broken out in windy conditions.
Ideally, plants should have been staked at the time of planting in late spring. If you haven’t done this, do so now, being careful not to damage the roots as you insert a cane as close to the plant base as possible. Larger plants may need several stakes.
Regularly tie stems to stakes at 10-12in (25-30cm) intervals as they grow .
THINNING AND DISBUDDING
To get good, long dahlia stems and larger (but fewer) flowers, all side growths appearing 18-24in (45-60cm) below the tip should be cut or broken out . This gives ample length for cutting and also allows lower shoots to go on growing and provide replacement stems. Do this once a week to reduce wasted energy.
Disbudding comes next. Retain just the terminal (top) bud and pinch out all the other flower buds immediately below to ensure large, blowsy blooms.
DAHLIA PEST CONTROL
Earwigs eat ragged holes in young dahlia foliage and their flowers, mainly during the night. During the day they hide amongst the foliage or flowers of host plants, or in other dark crevices.
Create an earwig trap by filling a small pot with crumpled newspaper. Sit the pot on top of a cane next to the dahlia. Each day, shake out the paper and destroy any insects lurking inside it.
AND THE OTHER ESSENTIAL TIPS…
Water whenever the soil becomes dry. This may be every day during a hot or dry spell. Mulching can reduce frequency.
The best dahlias have a good supply of well-rotted manure placed around the bases soon after planting. Whether you have supplied this or not, the plants should also be fed every few weeks throughout the growing season. Alternate between a seaweed tonic (such as Maxicrop) and a potash-rich tomato feed.
Keep weeds at bay with regular hoeing (be careful not to slice into the base of the dahlia). Again mulching will help suppress weeds.
Dig up and burn any dahlias with stunted or mottled foliage, which probably indicates a virus infection