How to grow borage
Borage is an easily-grown herb used in informal areas such as cottage gardens, wildlife areas and vegetable patches. The usually sky blue flowers are edible and can garnish summer drinks and salads. Borage is an annual so will need to be raised from seeds or young plants each year. However, there's also one perennial to look out for, which is also edible.
- Easy to grow, in most garden soils
- The herb borage is an annual
- Edible flowers are produced in summer
- Best on a sunny site
- Attractive to pollinating insects
- Self-seeds readily or collect seed and sow in spring
All you need to know
What is borage?
Borage is best known as a herb, grown for it's delicate blue flowers. These are plucked from the plant and sprinkled into summer drinks, such as fruit punch, where they add a refreshing cucumber-like fragrance.
This plant is an annual, so raise plants each year, or allow it to grow from the seeds that the plants will drop in the ground each year. It is easy to grow.
There are a few other, not-widely-grown borage relatives that we explain in the section on choosing below.
Choosing borage for you garden
Here are some things to consider when choosing borage for your garden.
Commonly seen borage (Borago officionalis) is a blue-flowered annua and is usually raised from seed, although yound plants are available in spring and early summer. Additionally, Borago officionalis 'Alba' offers pure white blooms and B. officionalis 'Bill Archer' has cream variegated leaves.
It's worth noting the size so that you can give new plants enough room to grow and bloom in your garden.
- Borage (Borago officinalis) reaches 50-70cm (20-28in) tall, and makes a handsome, erect plant. They are shorter if the soil is dry or poor - and seedlings that germinate later in summer usually flower but will also be shorter than those that germinate in spring
- Hardy perennial B. pygmaea is a hardy perennial that only reaches 30cm (1ft) tall and has a creeping habit
You can buy borage (Borago officinalis) as young plants in 9cm (3½in) pots or as packets of seed for sowing in spring. Look for B. pygmaea growing in containers in the perennials (rather than the herb) section of a garden centre.
Where to plant
Borage likes to grow in full sun in the ground, but will tolerate light shade. They will grow on any soil that is not waterlogged and like moist soil in summer to produce the biggest, best plants.
You can grow boarage easily in containers too. They are quite large plants, so use a pot at least 30cm (1ft) wide to ensure it's big enough to support it's size and weight.
When to plant
Plant young plants and sow seed of borage directly in the ground in spring (April/May).
How to plantIn the ground
Young borage plants are easy to plant in the garden, as you simply need to dig a hole large enough to take the roots, firm back the surround soil and water. The soil doesn't have to be improved with organic matter but, if you do, it will certainly help your plants to grow bigger. Plants should be spaced about 50cm (20in) apart.
To sow the seeds in spring, see Propagation below.
Pot up borage using a multi-purpose peat-free compost. You can also sow seed directly into the surface of the compost in spring, see Propagation below. You'll only have room for one borage plant per 30cm (1ft) pot.
WateringIn the ground
Generally borages in the ground will not need watering, but they do prefer the soil to be moist, and watering in dry spells will encourage the plants to grow to a large size.
Borages in containers will need the compost to be kept moist, which can sometimes mean watering every day in summer.
Borages are not hungry plants and don’t usually need additional feeding
However, when growing in poor or sandy soil, you can give plants a boost by feeding in spring with a general fertiliser, such as Growmore or fish, blood and bone. Always follow the instructions on the packet
Borages growing in containers should be fed annually in spring, as the nutrients in the compost soon run out (usually after about six weeks).
Caring for old plants
Dig or pull up plants after flowering, or when they start to look a bit tatty. You can collect seed to sow the following spring in pots or scatter on open ground.
Spring sown/planted borage will often being to look the worst for wear by August, so it's worth knowing they don't last all summer long. If you put these up, it's common for seedlings to quickly grow and take over the space, giving you flower again from September. To ensure this happens, keep the seedlings watered to encourage good growth.
If don't want plants to self seed, pull up the borage after flowering. You will usually have ripe seed from the early flowers by the time the last flowers fade and left to its own devices borage will seed about.
Tidy away the remains of perennial B. pygmaea by cutting down in autumn. It will resprout in spring.
Growing from seed
Borages are very easily to grow from seed and you don't need a greenhouse to raise them. You can buy packets of seed or sow seed you have collected yourself.See our sowing hardy annuals guides below, for full step-by-step details, but here are a few extra on seed collecting and growing tips:
- Collect the ripe seeds are hard and black, and contained within the remains of the old flowers. These appear as the flowers fade from mid summer. Simply pick out or shake off the seed into a paper bag
- Store the ripe, dry seeds in a tin in a cool room, or in an air tight container in the fridge
- In April, sow them in seed trays and pots, then keep at a temperature of 15˚C (59˚F), and plant these out when large enough to handle.
- Alternatively, sow the seeds directly in the ground - this is often the easiest method.
- The herb borage can get powdery mildew later in summer. This is usually when the plants have largely finished flowering, so simply pull up these plants and compost
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