March for the summer bulbs

MARCH FOR THE SUMMER BULBS
During the month of March the northern hemisphere spring equinox occurs, thus the length of
daylight is equal to that of darkness. From then onwards the daylight hours increase and the
gardening season is well and truly upon us and no doubt a floriferous spring and summer to look
forward to.

A variety of summer bloom can come from the bulbous plants and the month of March is ideal to
plant the following popular bulbs:

- Dahlias
- Gladioli
- Begonias
- Crocosmia
- Cannas Lily

All of the above can be regarded as sub-tropical plants, which thrive in the sunny and warm
locations of the garden. Therefore, it is best to take heed of the weather forecast and not to proceed
with planting if a frost is imminent.

Essentially the difference between spring bulbs and summer bulbs is that the spring bulbs require
several weeks of cold temperatures to trigger the upward growth, hence they are planted in autumn
and remain in the soil throughout the winter with growth and blossom occurring in spring.
However, the summer bulbs with their preference for a warmer climate do not require this slumber
period of cold temperatures.

The term bulb is used generically as it includes bulbs, tubers, corms and rhizomes. They are all
underground storage organs, the correct name which classifies them all under one umbrella is
‘Geophytes’ originating from Greek, earth (Geo) and plant (phytes).

The planting depths can vary depending on the type of bulb, a good rule of thumb is two to three
times the size of the bulb which more than often equates to planting approximately 100mm deep.
Dahlias are root tubers and can benefit from being pot planted in a greenhouse for the initial growth
to commence and then transplanted into the garden, this is to ensure they do not succumb to any
frosts. It is however, the temperature of the soil, a minimum of 13c and not the air temperature
which contributes to healthy and beautiful dahlias, therefore, it is best to choose an area with full
sun and lighter, free drainage soil.

Gladioli and Crocosmias are both corms and to be planted approximately 100mm deep and it is
advisable to prepare the planting bed by adding some compost after loosening the soil with a garden
fork. The Crocosmia corms will benefit from being planted in clumps, whereas, the Gladioli should
be planted individually with the point of the corm facing upwards and by placing several in close
vicinity to one another, one will be rewarded with a fabulous display of blossom. Gladioli also
make excellent cut flowers for the enthusiastic florists amongst us.

Begonia tubers are suited for containers and hanging baskets and will provide a continuous colour
throughout the summer and autumn. The fibrous rooted variety are more suitable for the garden
beds. The tubers have a convex side which is planted downwards, the concave side will posses the
new growth and faces upwards. Plant in a pot with a thin layer of gravel/shingle to allow for
drainage then the remainder with compost and plant the tuber just beneath the surface.

The range of colourful begonias available ensure hanging baskets are a great addition to any garden.
The canna lily is a rhizome (underground stem) and the large bold tropical leaves and striking
flowers make for a terrific display and should be planted in full sun and a sheltered location away
from strong winds. Plant the rhizomes, with the growing points facing upwards, 100mm deep with
500mm spacing between each one for a superb summer display and then water thoroughly.
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It is highly recommended to use a soil thermometer probe before the planting of summer bulbs, then
one can be sure the necessary soil temperature of 13c has been reached for a successful summer
bloom.

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