Submitted by Becki deNeui-Lynch, Master Gardener
We have two topics this week as identified by questions to the Master Gardener Hortline. Remember, an easy resource to call with your tree/plant questions is the Hortline at (319) 447-0647. If they are not open, just leave a detailed message and the Master Gardeners will get back to you.
- Understory trees and shrubs – the basics:
- Range in height from 3’ to 30’.
- *Found either partially or fully shaded by canopy trees, or on edges of canopy tree rows.
- *Many bloom in spring before the canopy is fully mature and provide a nectar punch for pollinators. Always check on sun exposure for shrubs, as some require 6-8 hours.
- *Do NOT buy “clean” hybrids – they are worthless for pollinators.
- *Follow planting directions closely for both depth and placement on property.
- Some of the BEST trees/shrubs for pollinators are:
- Native Crabapples – 15 – 25 ft. – Blooms spring –Supports 300+ pollinators
- Native Hawthorns – 15 – 30 ft. – Blooms spring – 300+ pollinators
- Rubus Blackberry – 3 – 8 ft. – Blooms spring
- Native Flowering Dogwoods – 12 – 36 ft. – Various bloom times spring/summer
- Eastern Redbud – 15 – 30 ft. – Blooms early spring
- Sericeberrys – 15 – 30 ft. – Blooms spring
- Spireas – 3 – 15 ft. – Various bloom times spring/summer
By planning for 3-6 diverse canopy/understory trees, and 3-5 shrubs which bloom at sequential times over the season, your property will have the strong bones of a healthy pollinator habitat. Simply review those trees/shrubs that survived the derecho, and add to them. Next week, I’ll list the native plants that bring the host color and nectar to your garden through the Fall.
- Hosta – “To Move or Not to Move”
The Hortline has received a number of questions regarding hosta that were once shaded, and now are in full sun. Should they be moved? And when? For those of you who know the names of each of your cultivars, I’m sure you already know which can handle more sun exposure. However, for those like me, who have no idea about most of them, here are the general guidelines.
- Hosta can be easily moved in September/early October and in April/May. Because of the angle of the sun, weather temperatures, and lack of canopy in early spring, they could all wait until then to see if the canopy tree protecting them survived.
BUT – where the tree is destroyed and already gone, here are some GENERAL tips:
- Google and follow transplanting instructions closely.
- Overall, the key to a healthy hosta is a combination of sunlight, soil, and CONSISTENT moisture.
- Most hosta require at least speckled sun and are tolerant of full sun for 3-4 hours in the morning, when temperatures are lower. Full afternoon sun for more than 2-3 hours will burn and dehydrate most hosta.
- The single colored green/dark green, blue, and crinkled leaf hosta are LESS adaptable to additional sun exposure. If the edges begin to brown and crinkle, or the leaves wilt, they should be moved immediately.
- Multi-colored hosta, and in particular white/green, are adaptable to more sun, and can vary widely with regard to moisture needs so watch closely and then decide if a move is necessary.
- White/gold/yellow/light green are the hosta colors which have shown the most adaptability to the sun and some are even advertised as sun hosta. These hosta can definitely wait until next season for a decision to move.
Hosta are one of the easiest non-native plants to grow and maintain. And, their blooms contain nectar for pollinators, particularly the fragrant ones. Hosta plantaginea is my all-time favorite pollinator hosta with it’s bright green shiny leaves and long tubular fragrant blooms. It blooms in mid/late summer and is welcomed by the bees as the mid-summer nectar feast is fading.
Next week: Repairing compacted earth and regrowing grass