No Growth of perennial seeds in containers *


So, I’m having trouble getting seeds growing on the rooftop of my low rise building. I go up there everyday to water with the watering can. I have sowed wildflower seeds in most of the containers, big & small, up there; there’s about a dozen garden containers in total. I do see the beginnings of growth in one very large container (that is 5′ x 5′) but mostly there is absolutely no growth. I thought that my first batch of seeds were nothing but duds (because of no success on the rooftop); I got a new box of wildflower seeds & sowed them again; there’s very limited success this time. Some of the soil is new this year. Possible issues: 1. Very strong sun up there 2. Watering process is not all that gentle . What is stopping the growth from happening up there?



Thank you for contacting the Toronto Master Gardeners with your gardening inquiry.

As our outdoor gardening space becomes limited, we are seeing an increase in the popularity of container gardening. There are many advantages to container gardening: containers  do not need much weeding; they can be placed at a height that can minimize bending for watering and tending; movable containers can “follow the sun” if you have changing exposure; and just about any flower or vegetable can be grown in a container.

It is difficult to exactly pinpoint the reason that you are not having success with your containers, however the following are some basic principles for successful  container gardening.

The first important factor to consider is the container itself. Be sure that your container allows for drainage when you water which will allow adequate air to be available for the roots. If the pot doesn’t have a drainage hole in the bottom, add one.

When choosing what to use to fill containers, never use regular garden soil. Garden soils are too heavy for container gardening and this will impede both drainage and aeration which leads to poorly growing plants or plants not growing at all. Soils for containers are always modified in some way to ensure proper drainage and aeration. Container soils are often referred to as soilless mix.

Thoroughly water the soil before planting. Water gently until water drains from the bottom of the pot. Plant seeds then water immediately after planting the seeds.

When considering the light conditions in your planting area, don’t overlook the absorption of heat by dark-colored containers. Dark-colored containers exposed to full summer sun can get so hot that roots are damaged and the potting media dries out very quickly.

For more information on container gardening please see: Successful Container Gardens 

Good Luck with your containers.