Stone seeds, Lithodora diffusa – care and cutting

Lithodora grows herbaceous, very flat and forms dense cushions. The plant rarely grows taller than 15 cm, but it spreads abundantly in terms of area. The numerous star-like flowers appear from May, at the latest in June. The flower colors vary from white to solid blue and two-tone blue-white.

The stone seed is quite hardy, even though the plant comes from southern Europe (Spain). It can happen that individual shoots die off over the winter, but the plant will reliably sprout again in spring. But you have to be careful, because there are differences in winter hardiness. Not all of the species are equally hardy.

The stone seed is suitable for the stone or heather garden, for slope and wall greening, can be planted in containers and makes a good ground cover. For perennial beds and borders, Lithodora diffusa is only suitable for planting in the foreground, otherwise it will perish.

sorts

There are a few varieties, but many look very similar. The layman will often not be able to tell the difference at all, unless the flowers are white or two-tone. I personally find these blue and white varieties the most beautiful, although I have the common blue variety ‘Havenly Blue’ in the garden.

• Diffuse Lithodora
  • ‘Alba’ – white flowers
  • ‘Snow’ – white flowers
  • ‘Cambridge Blue’ – medium blue flowers
  • ‘Grace Ward’ – blue flowers
  • ‘Star’ – white-blue flowers, created by natural mutation
  • ‘Havenly Blue’ – bright gentian blue, single bloom flowers, 15 cm high
• Lithodora hispidula – 40 to 70 cm tall species, not hardy, white, pendulous flowers that turn slightly pink over time
• Lithodora oleifolia – very similar to Lithodora diffusa

Caring for the stone seeds

The stone seed is quite easy to care for. It needs sufficient sun, warmth and an acidic, but lime-free substrate. Otherwise, it is a frugal plant that largely gets by without care. After winter it can happen that some of the long shoots are brown and you have to cut them, but you don’t have to worry about anything further. If you provide the other plants with water in summer when it is dry, the stone seeds should not be forgotten and fertilization at the beginning of the growing season is also good. Otherwise Lithodora diffusa is a sure-fire success.

location

In terms of location, it is important that the stone seed is warm and sunny. It doesn’t have to be bright midday sun, but the plant does need a few hours of sunlight. Wind shouldn’t be so cheap. I live in a very windy corner and I can’t say that the Steiname doesn’t like it with me. It grows and thrives. I have to admit, however, that there is a bush in the direction from which the wind usually comes. So it is somewhat protected, although the witch hazel is not that dense.

• Full sun
• Warm
• Sheltered from the wind

Plant substrate

The plant substrate is very important for whether the stone seed feels comfortable or not. In calcareous soils, Lithodora diffusa has no chance. In return, the plant likes a somewhat acidic substrate. If the location and the earth are right, the rest of the maintenance will take care of itself. Otherwise, the stone seed is not demanding.

• Well-drained and nutrient-rich soil, but fresh
• An acidic and lime-free substrate is important. A heather garden therefore offers the best conditions.
• Clay soil is unfavorable because the plants usually do not survive for long. It absolutely has to be made more permeable. Work in lots of sand and humus!

plant

When planting, it is important that compost is incorporated, regardless of whether the soil is very loamy or very sandy. Compost is always good. Otherwise, not much needs to be considered when planting. As always, it is a good idea to put the root ball in water before planting so that it can soak up properly. Even after the planting campaign, provide the plants with a good supply of water.

• Incorporate compost when planting
• Making heavy soils more permeable – sand, grit, or gravel
• Can be planted all year round, although this is not recommended in winter
• Plant spacing 20 to 30 cm
• About 8 plants per square meter
• The top of the ball should be slightly below the surface of the soil
• Water well after planting

Watering and fertilizing

The stone seed is not one of the plants that need a lot of water. It can cope with drought quite well, at least when it is well grown. It is enough to water it with the other plants once you are at it. It’s robust in that regard. Fertilizer is not needed very much either. Add slow release fertilizer at the beginning of the season and that’s it. I used horn shavings and Lithodora diffusa is growing and thriving.

• Don’t need a lot of water
• Drought is not a problem
• However, the soil should not dry out completely
• Lack of water is shown by limp leaves. If this is the case, watering is advisable.
• Do not water in the sun, this will cause burns. Watering morning and evening is always better.
• Watering in the morning is recommended because the wet leaves dry off faster. This prevents fungal infestation.
• Provide nutrients with slow release fertilizer in spring

To cut

Can or does not have to be cut. It is always a matter of discretion. Brown shoots should of course be removed if no more greenery wants to sprout. I always wait to see if something happens and usually the stone seed drives out again. The fresh green then covers the brown and you can no longer see anything. If you cut off the brown shoot too early, it will take time for the area to grow back, but it still happens quite quickly.

• The shoots can be cut back after flowering. You only cut if you have to, otherwise the Lithodora can grow.
• Proper pruning can be done every two to three years. The plant then produces stronger shoots again.
• Especially with young plants, it is advisable to cut back some shoots from time to time so that they branch better and the cushion becomes denser.

Overwinter

When overwintering, it depends on the variety. Not all are sufficiently hardy. I have ‘Havenly Blue’ and I never cover. However, I live in the very mild Lower Saxony. We rarely have more than -10 ° C. The sun doesn’t really get to where my plants are in winter, so the sticks are not so important. In any case, the plant survives the winter quite well. Some shoots are brown, but I think that’s not the frost. The stone seed must also renew itself. It does not bother me.

• Brushwood as winter protection is recommended
• Definitely sun protection in case of freezing temperatures

Multiply

Propagation is quite easy. You use cuttings. The shoots should not be completely lignified. Otherwise it is possible without any problems. You can also divide the plants in autumn. I haven’t done that yet. You have to untangle the long shoots. I think a lot of them break. So, personally, I would prefer propagation from cuttings and will tackle it this year.

• Cuttings from March to September – take root easily
• Share in autumn

Diseases and pests

As for diseases, the stone seed is very robust. He is also not immune to fungi, but serious diseases are rare. Pests are also rather rare.

• Snails – do not eat the woody shoots and the rather hard leaves, but like to build their nests under the protective layer. In summer you can find lots of baby snails. The only thing that helps here is collecting. Young Lithodora leaves do not disdain the snails either. For that reason alone, you have to do something about the nuisances.
• Soil that is too wet can mean that the plants cannot survive the winter. It can be advisable to cover the soil, or the plant at the same time, so that all the moisture does not get into the soil.

Conclusion
Lithodora diffusa is a very decorative, evergreen plant. During the flowering period, the whole green cushion turns into a blue flower surface, very decorative. The plants are quite undemanding and easy to care for, and with the right location and substrate they can get along on their own. I can only recommend this plant, especially as a ground cover for larger areas. However, I would also plant others in between so that flowers are available for a longer period of time. The flowering time of the stone seeds is not really long. Otherwise, I can unreservedly recommend the plant.