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Spring temperature changes can be problematic for some plants

Beware of spring weather as it can change from warm to cold quickly. While there is an desire to put out bedding-out plants, it is not a great idea as temperatures still drop below freezing at night.With the exception of pansies, bedding-out-plants should not be put out for another week or two unless they are in a protected area or given extra protection when needed.
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Beware of spring weather as it can change from warm to cold quickly. While there is an desire to put out bedding-out plants, it is not a great idea as temperatures still drop below freezing at night.

With the exception of pansies, bedding-out-plants should not be put out for another week or two unless they are in a protected area or given extra protection when needed.

Frost protection can be as simple as a warm area of the yard or being covered with a polyspun cloth, paper, a tarp or plastic. Plastic only works if it doesn’t touch the plants.

Covering plants every night is labour intensive.

There are other plants, such petunias and snapdragons, that are frost tolerant but will not thrive under cold conditions. These and other annual plants will do better if they are left in a greenhouse or warm area until they are to be planted out.

Purchase annuals about a week before they are going to be put in the garden. Plants suffer less setback or transplant shock if they become acclimatized before they are planted outside in a process gardeners call hardening off.

Start the process by placing the plants outside in the sunshine for a few hours on a warm day, then moving them back inside. As long as the plants do not develop any white burn spots, leave the plants outside for a longer period each day until they are always outside.

Once the danger of regular frost is past, plant the plants in the garden.

The date for setting out plants will change with each region and most homeowners have their plants in before municipal parks departments, which wait until the first of June to begin planting.

Perennials that were being grown inside a greenhouse will need to be hardened off, similar to annual plants.

Perennials that are in an outside area of the garden centre are already hardened off and can be planted outside immediately.

Seeds, with the exception of squash, cucumbers and watermelon, can be planted any time. They may not germinate until the soil warms but they are unlikely to rot. Plants such as nasturtiums, annual bachelor buttons, sunflowers and annual poppies grow quickly from seed.

Check the moisture levels of flowerbeds and water as needed. Usually at this time of year, there has been enough rain or late snowfalls to soak the ground, but this year moisture has been patchy. Soaking dry beds will encourage plants to put on new growth.

If winter protective mulch is still in place, remove it. Plants that are still covered with mulch will be lagging behind the ones that are free of mulch. Mulch acts as an insulator by keeping the soil warmer in the winter and cooler in the summer. When protective mulch is left on too long in the spring, the plants underneath can become hot and mould.

Spring is a great time to dig, split and move perennials. The plant’s root structure determines how to split a perennial. Perennials that grow in a compact circle are split by cutting the root ball in a number of pieces. Each piece must contain an eye or plant stock to produce new growth.

Ground covers either creep along the top of the ground or spread by underground runners. Plants that creep along the ground have shallow roots. Cutting a portion of the plant, including roots, off from the main plant is usually enough to start a new plant.

Plants with rhizomes roots are very easy to split. All it takes is a piece of root with an eye or sprout heading upwards and a new plant is formed.

Perennials only need to be split if part of the plant, usually the centre, dies or they become too large for their spot in the garden. When part of the plant dies, dig up the complete plant, remove all the dead sections and replant the living portions. If there are more plants than fit into the garden, share with friends, neighbours and local plant exchanges.

When plants become too big, remove part of the plant to be replanted elsewhere.

Spring is a busy time in the garden. Take care of the perennials now and the annuals when the weather warms.

Linda Tomlinson is a horticulturalist who lives near Rocky Mountain House. She can be reached at your_garden@hotmail.com.