The third week of June is when growth surges on bedding plants and perennials so fertilizing now will give you and your plants almost instant gratification. Heavy feeders like roses, petunias, geraniums and impatiens will branch out and bloom almost immediately after you fertilize. This is also a good time to pinch back leggy plants to encourage more compact growth. You can nip off the top one third of plants like chrysanthemums, sedum Autumn Joy, phlox and snapdragons now and you’ll enjoy more numerous blooms later in the season.
Buy perennials in gallon-sized containers this week and you can plant them directly into the ground or transplant into larger pots. You’ll find shade-lovers like hosta, astilbe and brunnera looking great in containers and are easy to transfer into your garden beds, as long as you follow these perennial planting tips:
1. Before leaving the nursery or garden center, check all new plants for hitchhiking weeds and slugs. The often-cursed shot weed is an import that we all brought home in nursery pots. Look under the leaves and in the drainage holes of pots for hidden pests.
2. Once home, soak the soil of your potted perennial before you plant. You may need to immerse the entire pot into a larger bucket if the peat-based potting soil in the container is so dry it resists absorbing moisture. If you use a watering can, add the water slowly, let it seep into the entire root ball and then water it again.
3. Next, dig the hole for the new plant. Remember that making a hole wider is more important than making it deeper. Add a shovel full of compost or peat moss to the planting soil and mix the soil amendments with the existing soil. Add water to the planting hole and let it seep in – yes, before you add the plant.
4. Finally, you can remove the plant from the pot. You don’t want to expose the roots to sunlight until the very last minute. Roots are like vampires – they find sunlight painful. If a well-rooted plant is stuck in the gallon-sized nursery pot you can usually loosen things by squeezing the sides of the pot. Then turn the entire pot upside down and bang the edge of the pot on a table or the edge of a wheelbarrow. It should slide right out.
5. Position the new plant into the hole so it is growing at the same level it was in the pot. If the roots are thick and packed, roughen them up with a garden trowel or clip a few near the sides. This will encourage more branching below.
6. Fill in around the new plant with soil, creating a bit of a basin but do not tamp on the soil with your foot. Press very gently with your hands. Too much pressure on the topsoil will squeeze out the air pockets and compacted soil not only struggles to absorb water, it also encourages deep-rooted weeds like dandelions.
7. Pour water slowly into the soil basin or slight depression formed around the new plant. I don’t like to use fertilizer on newly-planted perennials unless it is a slow-release fertilizer like alfalfa, Osmocote or fish fertilizer. Give the newcomers a chance to settle in a bit before stuffing them full of food.
8. Finally, add the frosting. A light topping of mulch, like bark chips or composted steer manure, will seal in the moisture and act as a security blanket to welcome your newly-planted perennial to the bed.