Greenhouse Weekend Duty Blog - February 16-18, 2018

Taylor Shpak & Chris MacDonald

This weekend at the greenhouse, we prepared for spring! On Friday, we potted up mixed
plantings for hanging baskets, featuring begonias, petunias, coleus, and asparagus fern, that
promise to fill out into some of the best-looking arrangements we have put together yet!

We also received a shipment of Alocasia seedlings. These were the ‘Calidora’ cultivar, which
usually reach heights of 5-7 feet at maturity, and boast large, showy foliage.

The main focus at this time of year in the greenhouse is our Hydrangea crop. The cultivars on
selection this year include Early Blue, Vanilla Sky, Rosa, and Chique. In order to achieve the
stunning blue colour of Hydrangea macrophylla ‘Early Blue’, special attention must be paid to
keep the pH of the soil acidic for the plant to produce blue sepals.
Horticulturists have been using aluminum sulphate for years to increase the acidity of their
growing media in order to produce blue hydrangeas, but did you know that the hydrangea
evolved this reaction as a survival tactic? Many plants are unable to grow in soils with a high
aluminum content, but the molecule anthocyanin -- the presence of which makes the sepals
pink or red by default -- is able to bond at the molecular level with the aluminum in the soil,
negating the damaging effects a high aluminum content usually has on a plant (Kimlicka, 2014).
A great example of nature’s resiliency, with a colourful side effect! We look forward to seeing the
results of our work in the coming weeks as the hydrangeas mature.

On Saturday, we turned our attention to making sure all plants in the greenhouse were at their
best. Walking the crops and spot-watering the places that are often overlooked during the
course of a busy week is important to make sure there are no neglected plants that could be
wilting, or otherwise damaged. Here is some Pennisetum setaceum 'Rubrum' that we spent time
cleaning up on Saturday.

Continuing with the theme of spring preparation, on Sunday, we planted Colocasia corms.
Colocasia esculenta, also known as Elephant’s Ear, is a tropical plant that reproduces via thick
underground root systems, similar to a bulb or tuber, known as corms. Elephant’s Ear corms are
edible, and used across the globe in many cuisines-- sometimes prepared similarly to potatoes,
and even used in sweet desserts & drinks like bubble tea!
Overall, our weekend in the greenhouse went smoothly and provided us with a unique
opportunity to learn how incredible plants are at adapting to their environment, as well as some
interesting insight into how they function at a molecular level.