Looking after

Hostas

There is a wide range of Hostas originating in the Orient and brought over to Europe in the 1700s, there are currently many thousands of cultivars with new ones being added all the time. They have a vast variety of leaf shape, size and texture coming from a wide range of environments. Variety of Sizes Mini Height 15cm Small Height 15cm to 25cm Medium Height 25cm to 45cm Large Height 45cm to 70cm Very Large Height +70cm Variety of Colours Hosta leaf colours range from green, blue, gold, yellow to white and countless variegated varieties. Variety of Leaf Shapes Hostas are known mostly for their durable, colourful foliage. There is no shortage of leaf shapes including heart-shaped, narrow, smooth, puckered, elongated, oval, rounded and mouse ear shaped. While Hostas are considered easy to grow, it helps to know a little about how to grow them so that you can help them reach their full potential. 1. General conditions As a general rule Hostas need fertile soil, heavier rather than lighter. Slightly acidic, pH 6.0 to neutral pH 7.0, some shade and shelter from wind. It should be noted that Hostas in pots have different requirements to those planted in the ground and the miniature Hostas require a little more care, as it was related to me by one Hosta grower that they can become scared of too big a pot. 2. Where to Grow Hostas Although Hostas are known for being shade lovers their sunlight requirement varies widely, and the same variety of Hosta can produce different colouring depending on the quantity of light they receive, becoming deeper coloured in the shade, whilst lightning quite markedly in the sun. A general rule of thumb is that the lighter the foliage the brighter the sun can be received, the darker the foliage the more protection from sun is required. It is also generally recommended that Hostas are best located where they can receive morning sun and protected from afternoon sun, especially in hot locations which can stress Hosta plants and fade or burn their leaves. 3. Pests and Diseases Hostas are noted for suffering from Slugs and Snails Protection against slugs and snails starts in March before the leaves have appeared. • Remove garden debris to reduce the places that slugs and snails have to hide. They normally like to spend the day out of site. • If in the ground use crushed egg shells, or horticultural grit to make an abrasive surface. • If in a pot you can use horticultural grit on the surface of the pot, or put a band of copper around the pot to reduce them climbing. (Please note that slugs can climb through the soil of a pot and they tend to lay their eggs inside) • Another method is to make and spray a dilute garlic solution weekly on your Hostas. It takes a few weeks for this to begin working, but it irritates the slugs and snails, and they leave your Hostas alone. Also when it gets into the soil it kills their eggs. • Nematodes are a natural microscopic organism occurring naturally in the soil. They attack the slugs and kill them slowly. One treatment should last the season. See • https://www.agricentre.basf.co.uk/en/Products/Overview/Nemaslug.html and can be purchased from reputable suppliers. • Nightly excursions to remove slugs and snails from the leaves. Note: We do not use Slug pellets as it is a mixed blessing. The slug pellets kills the slugs and snails, but is also an attractant to them, so if used too much will draw them to the plant you are trying to protect. We also don’t use them as we have ducks to control the overall population. A client of ours doesn’t use them and states that since he stopped more and more hedgehogs have come into his garden and he no longer has a slug or snail problem. I should say that he does live in a village situation. Crown Rot is one of the few diseases to attack plants, usually in the dormant season, but is caused by a fungus which likes damp conditions. To help prevent this do not water directly into the centre of the Hosta, and ensure good drainage. Further reading on this problem is available from an article by the Iowa State University: https://hortnews.extension.iastate.edu/2009/7-15/petiolerot.html 4. Seasonal Care Spring Care Water: On average Hostas require about 2.5cm of water per week, either by watering or rain. It is recommended not to water Hostas in spring until the frosts have passed and the chances of root rot is diminished. General rule of thumb is that Hostas do not like being water-logged. Soil and feed: The addition of some compost worked into the soil helps with early growth. Apply a slow release fertilizer in spring to give the plants the boost for the beginning of the growing season, making sure that it does not touch and burn the leaves, or buds of the Hosta. In pots you can use a liquid fertilizer every few weeks. Protection: Don’t forget that during this phase the plants can still be frosted and their early leaves may get scorched. Don’t use plastic directly on the plants as this can freeze directly to the plant. Now is the time to tidy and begin protecting the Hostas from slugs and snails. Summer Care Water: Lack of sufficient watering in a dry summer can cause the Hosta to go into dormancy where the outer leaves will wither and stop growing. Water regularly, without waterlogging and this will stop the plant from becoming stressed and will produce larger happier Hostas. Soil and feed: It is possible to feed your Hosta during the early part of the summer, but not recommended later, otherwise it may confuse the Hosta when it prepares for the Winter. Protection: If you have Hostas in pots it will be helpful to move them to a shadier part of the garden during the hot afternoon sun. Use some of the previously mentioned techniques to protect from slugs and snails. Autumn Care Water: As long as the Hosta leaves are green then continue watering the plant until they start to wither, as the plant will be producing the food stores for over wintering. Now is the time to consider removing pots out of trays and saucers to ensure the Hostas do not get waterlogged. Soil and feed: No fertilizer required so that the plant can prepare for winter. Protection: Prepare the Hostas for winter. There are 2 thoughts of removing the leaves, I am of the opinion that they should be removed carefully as this will remove slugs, snails and diseased leaves. You should consider mulching the Hosta to help protect them over winter. You could use leave mulch, straw and other biodegradable medium that allows for air pockets to help protection. Now is when slugs and snails lay eggs, so is another time to try and reduce the numbers in your garden. Winter Care Water: Protect from frost and waterlogging. Soil and feed: Nothing needed here. Protection: Keep them protected from the frost and complete freezing.