A Low growing plant that will look beautiful cascading over rock walls ,flowing out of baskets , or in a rock garden, Rock Cress Cascade Mix grows only 4 inches tall and produces mounds of blue, red, and purple flowers over the mat-forming evergreen foliage. Rock Cress is a popular spring-flowering rock garden perennial. It forms a low carpet of evergreen leaves, literally smothered by flowers for several weeks. This strain has single flowers in shades of deep purple to mauve, with a tiny yellow eye. Nice along pathway edges, rock walls, or in alpine containers. Plants should be trimmed lightly immediately after blooming, to encourage a thick mounding habit.A Perennial for zones 4-9. Ideally plant in loamy, sandy and clay soil and try to keep the ph of your soil between the range of 6.8 and 7.8 as Rock cress likes to be in weakly acidic soil - weakly alkaline soil. Keep in mind when planting that Rock cress is thought of as hardy, so this plant will grow or become dormant during the winter. Height of 4 inches that will spread to a width to 24 inches. Needs full to partial shade.
|How To Grow Arabis-Rock Cress from Seeds. |
They can be directly seeded into your flower garden, or seeded indoors for transplanting later. Sow Rock Cress seeds early in the season and press into soil lightly, as light is needed for germination.
If spring planting, sow seeds indoors in late winter, 8 to 10 weeks before transplanting outdoors in the spring (after danger of any frost and night time temperatures are in the upper 40's or warmer).
Germination will usually take 14-21 days at a fermination temperature of 68F.
Keep seeds moist until germination,
Lightly cover with peat moss to help retain moisture (you should still be able to see the seed through the peat moss). Bottom water or mist spray and try not to let the seed dry out. Keep trays at a consistent temperature according to what the seed packet specifies.
|Transplant into the garden 12 inches apart after frost danger has passed. |
- OR After frost season has passed, Rock Cress ground cover seeds can be directly sown into a prepared seedbed outdoors.
- Select a site that has good drainage and provides the amount of sun or shade needed. Raising the bed 2 - 4 inches above the original ground level will be helpful with drainage. Beds that provide good drainage are important as many ground covers do not do well with “wet feet,” and the poor drainage will cause rotting. Do not till the soil unless you plan on waiting about two months to plant so you can kill off all the weeds and grasses that will come up due to tilling.
- Prepare the seed bed by removing all weeds either with herbicides or pulling manually (preferred).
- Once the seed bed is prepared, spread a 1 - 2” layer of seed starting soil over the bed.
- Spread the seed over the desired planting area. Many of the seeds for ground cover are very tiny, and it is helpful to mix a seed packet with very fine sand or lime (if not using Shake n' Seed). This gives you more matter to spread over the desired area. If you are needing to sow between stones, using a parmesan cheese can is a good way of controlling where the seed/sand mixture goes, and it allows you to get into the small crevices.
- Use a light dusting of the potting soil or peat moss over the top of the seed, but do not cover more than the thickness of the seed with soil (follow packet instructions regarding planting depth). If using peat moss, you should still be able to see the seed through the peat moss. Tiny seed will NOT germinate if planted too deep!
- Moisten the seed bed with a fine spray mist or water weeping type hose and maintain the moisture until the seed has sprouted. This step is crucial. If planting outdoors in the hot summer months, watering once or twice a day is not good enough. You may need to water 4 or 5 times a day to keep the seed bed moist. Using water timers is a great way to accomplish this which you can purchase at any home improvement store. You can set the water timer to come on every couple of hours just for 2 minutes or so (depends on your soil) and it will keep the seed moist all day long. At night time the seed will stay moist so this is not necessary if you have it water once after it is dark. Ensure mist spraying as to not wash the seed away or cause it to be buried too deep.
- It is recommended to weed the bed as the seedlings grow as well as using a liquid fertilizer like our 3-18-18. Liquid Soil Aerator is also recommended for retaining soil moisture, adding organic matter to the soil, adding beneficial microbes, and keeping the soil friable.
- To ensure best planting, make sure you plant when it is warm outside. If spring planting, frost season should be well over and night time temps staying in the upper 40's or warmer (see packet directions for specific planting temperatures). If late summer planting, make sure you have 8 - 10 weeks before frost season begins. You can not plant ground cover seed in late fall/winter unless you are in a completely frost free zone.