Summer Bulbs Inspiration - The Garden House

Summer Bulbs 

One of the most common questions we are asked here at The Garden House is “What plant do you have which will flower all Summer long?” In short, there are very few plants which will flower for such an extended period. The reason is very simple. Flowering is the act of reproduction and the poor plant then requires a rest for what is in effect it`s pregnancy i.e to form a seed. There are however a few tricks which you can use to ensure long lasting Summer colour. A judicious choice of Summer flowering bulbs will provide colour from June through to the first heavy frosts in late Autumn.

The essential fact to understand about bulbs is that they are a bit like a Duracell battery. They are a store of energy which comes to life every year. They are really easy to grow and demand very little attention. Here are some tips to help you choose.


It might seem strange to think of gardening in terms of fashion. When I was a kid, which is longer ago than I care to admit, dahlias were a core plant in the Summer garden. They then went into a serious decline in popularity. Recently they have come back with a bang. The main reason is that the plant breeders have developed new colours, shapes and sizes, all with extended flowering periods. Growing them is a cinch. You can pot them up in a glass house or on a window sill in individual pots anytime form now onwards.  I use Jacks Magic in a pot size 3 to 5 litres. Half fill the pot with the compost. Pop in the tuber with the dangly bits (roots) facing downwards. Then top up the compost to form a ”collar” around the stem of the dahlia where it was cut back last year. Don’t worry if you are wondering how in the name of God you will know which end is which – it will be obvious. Keep the compost damp but not overly wet. It will seem as if nothing is happening for a while but then you will see them spring back into life after a few weeks. Up the watering now. When the risk of frost has passed in May you can transplant the dahlia into the ground where you want it to flower. Because many dahlias have large flowers they will need to be staked. The time to do this is when you transplant them not after the stems have fallen over following a heavy shower when the flower heads have become top heavy.

If you prefer, instead of bringing on the dahlia in a pot and then transplanting it, you can plant the tuber directly in the ground. This can be done from late April through June.

During the flowering period you should on a weekly basis deadhead the flowers which have finished flowering. This will encourage further flowers to form. Sometimes you can get confused whether a bud is about to flower or has finished flowering. The answer is easy – the bud which has finished flowering is cone shaped. The heavy frost will make the foliage go black. This is the time to cut the plant back to a few inches above the soil. Strictly speaking you should lift the tuber at this stage, dry if off and store in a dark dry corner of the shed. However I am lazy and take the chance that they will survive the Winter in the ground. In most years there is upwards of a 60% chance that they will reappear the following Spring. If you have heavy soil you might dig in some horticultural sand when first planting the dahlia as the improved drainage will increase the odds of the tuber overwintering successfully.

Dahlia flowers come in a few shapes. Pompom which have the wee tightly formed flowers. They have a very neat appearance. Cactus which are more shaggy in appearance. Dinner plate are as the name suggests very large showstoppers. You will definitely need to stake these well.

The undercarriage of a dahlia plant is not its most attractive feature so I tend to plant mine towards the back of the flower border. This way you get the benefit of the flowers.

A word of advice – do not go mad choosing every colour under the rainbow. Far more attractive to choose from a limited colour palette. We have selected our stock with this in mind. It will make choosing easier for you.


Begonias are among the most reliable of plants. It does not seem to matter whether it pours from the heavens or if the sun is splitting the sky they will flower their little heads off. Every September we travel over to Birmingham to a trade exhibition. The hotel we stay in plants up all their flower beds with begonias and every year without fail they are a riot of colour. Mainly used in container gardening once again growing them is easy. Just follow the instructions as for dahlias. The only difference is that the bulb is saucer shaped with a hollow on the top. Basically you place the bulb on the surface of the compost, drawing the compost up the sides of the bulb but not covering it. You can start them off indoors from March through April or directly outside in May.  The other difference of course is that they do not require staking. There are also trailing varieties which are perfect for hanging baskets.


These statuesque flowers are adored by flower arrangers. Their tall narrow stems carry a profusion of elegant flowers. They are incredibly easy to grow. You pop them directly into the ground and they will do the rest. Planting time is from March through May. There is no need to lift them out of the ground for the Winter. They will look after themselves. One thing you must remember is to stake them. Otherwise If like me you forget, they will flop over just when they start flowering. They look better planted in groups rather than singly.  

To achieve the ideal of all Summer long colour you can companion plant both dahlias and gladioli in your flower border. For best success either work with a complementary colour palette from the same side of the colour wheel or juxtapose colours form opposite sides of the colour wheel. Contrasting colours work well so you might try blue/purple with yellow/orange. This will give you a dramatic look. Alternatively you could go for a more muted look using pinks, whites, mauves and pale blue. This will give you a sophisticated look. Neither is right or wrong it is down to your own personal taste.

The other things to consider in your planting scheme are height, texture and shape. The contrast between a “blousy” dahlia against an elegant gladiolus can be remarkably effective.

When you are in with us you will find that we have stocked this year collections of bulbs which cater for:- bees and butterflies; the scented garden; the cut flower garden; complementary colours. 

We will be delighted to help you when you visit.

GardeningSummer bulbs