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What We've Included
When to Plant | Where to Plant | How to Plant | When to Water | Propagating | Common Diseases & Pests | When will they Flower?
When to Plant
Polemonium plants are best be planted in spring or autumn, if the soil outside is warm and moist. This gives them time to establish their roots before summer starts.
Where to Plant
Polemonium plants prefer a partially shaded area of the garden. This is because their soil then won’t dry out as often as those in full sun. The soil should always be moist, and they’re best suited to borders because of this.
How to Plant
Planting Polemonium from Pots
Our pot-grown plants are incredibly easy to plant and grow. Whether you’re growing them directly outside into the border or into a container, our pot-grown plants are a breeze from the moment they arrive.
- Dig a hole in the border that’s big enough to house the root system. If planting in pots, fill a large pot halfway with potting soil and then make a well in the middle. Do this until the top of the soil from the plant is just below the top of the pot.
- Wedge in the plant by adding soil to the gaps in the hole, firming down the surface to ensure it’s in place.
When to Water
Water Polemonium well, although take care not to water-log the soil as it can damage the plant. You won’t need to water them as much once they have established themselves and shouldn’t need feeding if grown in healthy soil.
Propagating
Jacob’s Ladder self-seeds, without encouragement. You can collect the seeds after the plants have died back, which look like dry brown pods. Sow them in autumn or winter undercover or outside in spring. These seeds won’t flower that same year but will produce foliage.
You can also divide plants, cutting the lifted plant into twos or threes and planting them elsewhere.
Common Diseases & Pests
Polemonium isn’t attacked often by any pests, but it can be victim to powdery mildew. This is when the plant doesn’t get enough airflow and becomes humid – producing a powder on the leaves and flowers. You can avoid this by ensuring they’re not planted too close together and avoiding watering the leaves.
When will they Flower?
Polemonium often appears from early summer, depending on the variety. We always recommend checking the product before planting to know the exact flowering times, as they may differ from type to type.