Planting Tips - Perennials
Plant at the right time
- Most resources advise the best time to plant is spring or fall and although this is generally true, there's a lot of advantages planting throughout the summer. Establishing perennials in warmer soils can promote faster root growth and in turn can be more successful than in cooler seasons.
Identify the location you want to plant on your property and ask the following questions
- How much sunlight does your planting location get per day?
- Does this area get normal levels of rainfall or is it in a location under overhangs or dense tree coverage?
- Do you have access to water?
- What's your soil like? Is it sandy and well-drained or heavy and holds moisture? If you are unsure try performing a water-holding capacity test
Know how big each perennial grows
- Check the height and spread measurements when planting a garden.
- Knowing the mature size will help in providing the correct space, this will allow for adequate air circulation and room for growth.
Match the perennial to the location you choose
- Select plants that are well-adapted to the local climate. Know your Zone
- Use the search filters to select appropriate plants for sunlight levels
- Use the search filters to select appropriate plants for soil moisture levels or amend the soil to increase or decrease water holding capacity
Determine the hole size required to plant
- The width of the hole should be two times the width of the root ball you are planting. This extra width allows the roots to easily spread out and establish themselves in the loose soil when you backfill the hole.
- The depth of the hole should be equal to the height of the plant's root ball.
Amending the soil
- In most circumstances it is beneficial to mix a composted manure or leaf waste with the existing soil before back filling. A recommended rate is 1 part compost to 4 parts existing soil.
- Fill the bottom of your hole (approximately 3-5cm) with the amended soil. The loose soil at the bottom will allow the roots to easily establish themselves.
Getting ready to plant
- Remove the container (packaging) by turning the plant upside-down holding the soil and plant in one hand and gently taping on the bottom of the container to free the container from the root ball. Do not pull the plant from the container as this may cause damage to the top growth and roots.
- Once the container is off do an inspection of the roots. If the plant has an established root system, break up the roots that are circling by gently disturbing the soil and roots with your fingers.
Planting time!
- Place the plant in the hole. Reassess that your hole depth is equal to the height of the root ball. Adjust by adding or removing soil from the bottom Note: It is okay for the root ball to be slightly above the height of the hole to allow for the soil and roots to settle after watering.
- Back fill with the amended soil to roughly half the hole depth.
- Use the end of your shovel to gently tamp the soil around your plant until you feel the plant is stable and vertical inside the hole. Adding water at this stage will help settle the soil and fill in any potential air pockets around your plant.
- Continue to add soil until it is filled to the top of the hole. Any extra soil can be displaced using a rake or removed and added to another garden.
Know when to water and how much
- Water newly planted perennials thoroughly after planting and continue until they are established. There are easy-to-use tools to measure soil moisture, although visual inspection and feeling the soil can be just as reliable.
- Consider time of year and weather conditions. Factors like temperature, humidity and rainfall influence how quickly the soil dries out.
- Adjust based on needs. Some perennials have specific water needs. Confirm the ones you chose and adjust accordingly.
- Mulching is optional although a layer of mulch around the base of the plant can help retain soil moisture and reduce the need to water as often. Note: Be careful not to apply mulch too heavy or bury the stems of perennials in a thick layer near the crown as this may cause disease or stems to rot.
- Morning waterings are preferred. Watering in the morning allows the plants to absorb moisture before the heat of the day evaporates it. Avoid watering in the evenings after the sun is down as this may promote fungal disease on foliage.
- Adjust as the plant establishes. Perennials will develop roots quickly (2-3 weeks) and will become more resilient to longer periods without watering. Keep monitoring and gradually adjust based on the plants growth and visual inspections.
Optional Tips
- Depending on the timing of when you receive your perennials, some may be full of flowers or flower buds. Pruning or removing some or all flowers out before planting can be beneficial as this can help reduce transplant shock. Perennials require a lot of energy to flower so by pruning back flowers and some foliage this will reallocate the energy towards establishing a strong root system. This is a strategy most growers use to establish roots in a container at the nursery and the same is true in the garden.
- Pruning can stimulate the growth of new shoots and branching which will help your perennials to become fuller over time.