Any plant that grows, flowers, produces seeds and dies over the course of one year is considered an annual.
Annuals are an excellent way to ensure colour in your yard all summer long. Use in borders, in beds or to fill open spaces between immature shrubs and trees. They over flow hanging baskets and window boxes, as well as creep up walls or trellises. The variety of uses and colour combinations is endless.
You can purchase annuals in both seed and seedling form. Sow seeds either indoors or outdoors, depending on the growth requirements of the individual plants. Annual seeds that require a longer period of growth should be started indoors. These plants are identified in the chart portion of the Annual section. With Calgary's short growing season, it's usually best to plant annuals in seedling form after the last chance of frost.
Note: When choosing a spot to plant, consider the annual's growth habit. Position tall plants at the back of beds where they will not block the view of smaller plants.
Introduce yourself to the new varieties of annuals each spring. Look for shade tolerant annuals for shady locations and sun loving annuals for hot, sunny locations. Decide where you require color in your yard for the months of May to September. For the best success choose vigorously growing plants that are dark green, short in height, and just about to bloom.
Garden and Bed Soil Preparation Ideally, soil preparation for the planting of seeds and seedlings will be done in the fall. If this is not possible, however, organic material, such as compost or manure, should be worked into the soil in the spring. This will help the soil retain moisture, improve drainage, add oxygen and improve root growth.
Fall soil preparation
Remove all garden debris from planting site and add to composter for future use.
Spread layer of organic material several inches thick over area. Compost or manure is ideal for this.
Turn organic material into existing soil using a gardening fork. Note: Large lumps should be left in the soil at this point. Frost helps to break soil into a less dense soil structure, ideal for plant growth and moisture retention.
Turn again in the spring, shortly before planting. Break down large lumps of soil with a garden fork.
Note: Slow release fertilizer can be turned into the garden at this point, if desired.
Spring soil preparation
Remove all garden debris from planting site a few weeks before planting.
Turn existing soil using gardening fork, breaking up lumps.
Add 4-6" of organic material and turn over again.
Note: Gypsum can be added to heavy clay soil to make it easier to dig in organic material.
Store bedding-out plants that can not be planted the same day they are purchased in a shady location. Water the packs or flats well to prevent wilting.
For instant results, or a quick start for plants that need more time to complete their life cycle than Calgary's climate allows, seedlings are the perfect fit. They can instantly add greenery and colour to your beds. In Calgary, spring frosts can last until late May. For that reason, many area gardeners wait until at least June 1 to plant their seedlings outdoors.
The best time to plant annuals is on evenings or cloudy days when it is cooler outside. If planting on warm, sunny days make sure that annuals are watered immediately. Apply a root start (10-60-10) which stimulates rooting. Individually packaged annuals are easy to remove from their packs for planting. If plants are not individually planted, gently separate one plant from another, keeping as much of the root ball together as possible. In either case plant the root ball just below the soil line. If annuals are planted in peat pots, plant the peat pot below the soil line to prevent the pot and the root system from drying out due to air exposure. Be sure to leave adequate room for annuals to develop.
Placement & Planting Tips
Place plants according to sun/shade tolerance. Also consider growing conditions, such as downspouts, and shady spots.
Plant slightly deeper than pot level, usually about 1cm. Cover the old root ball.
Start seeds indoors according to the seeding dates on pages 11 & 12 of this book. Beginning gardeners might want to try the Jiffy Professional Greenhouse.
Seeds for annuals can be planted outdoors as soon as the ground can be worked. McKenzie Seeds offers a huge variety of quality seeds.
Water slowly and deeply, soaking the root ball regularly depending on conditions. More water is required when the temperature is warmer.
Aerate the soil with the mineral Zeolite, which helps to promote the slower release of nutrients and also helps to break up clay.
Feed annuals with regularity using a good quality fertilizer. A good choice is Nurseryland Power Bloom.
Deadhead flowering annuals to extend the flowering season. Deadheading is removing spent flowers to encourage re-blooming.
Steps for planting seedlings
- Plan area to be planted.
- Work and condition soil.
- Dig a hole that will accommodate the seedling you wish to plant.
- Remove seedling from its flat or pot. Massage root ball gently. Plants that have roots that are crowded in their pots will benefit because the roots will sometimes continue to grow around in a circle, never reaching out for moisture or nutrients.
- Set plant in hole and add soil until the seedling is planted at the same level as it was in its container.
- Firm down soil around the seedling and water in well.
- Fertilize the plant with transplant fertilizer typically a higher middle number fertilizer like 10-52-10, 10-60-10 or Myke to help prevent transplant shock.
Note: Peat pots should always be removed since they do not degrade well in Calgary's short summer and often dry climate.
Seedlings grown indoors or in a greenhouse will need to be hardened off. Hardening off is the process of adapting a seedling grown indoors to the outdoors over the course of a couple of weeks. Differences in temperature and light intensity may set back plants and delay flowering if the plants are not gradually acclimated to both. To start, plants should be kept in a sheltered area away from intense sun and harsh winds. A cold frame is an excellent place to harden off your seedlings but any sheltered spot will work well. Plants should be covered or brought inside at night if temperature or wind conditions dictate. Over the course of two weeks, gradually increase the plants' exposure to the sun intensity and other elements. At this point, seedlings can be planted outside in beds or rows whenever weather will permit.
If you purchased your annuals at greengate, it's quite possible they have been hardening off in our open roof greenhouse. If you are unsure, check with our staff. Some annuals do not stay here long enough to be completely hardened off.
Annual plants post-planting care and watering
It is best to water early in the day and to keep plant foliage as dry as possible by watering at ground level. Water freshly planted annual bedding-out plants thoroughly to give them a good start. Thereafter, water when the soil surface dries out. It is best to water early in the day and to keep plant foliage as dry as possible by watering at ground level. Water droplets that remain on the foliage overnight encourage plant diseases to develop. Do not rely on rain to water your annuals sufficiently. It is important to observe the condition of your annuals often to ensure continued growth and satisfaction.
In order to induce continual vigorous growth, blooming and fullness, remove the terminal growth buds on tall lanky annuals by pinching them. Fertilize your annuals every three to four weeks with an all purpose, water soluble fertilizer such as a 20-30-20. Encourage repeat blooming by removing dead flowers (dead heading).
info coming soon