When do i plant sunflowers seeds

Sunflowers do not require fertilizing. However, because they grow vigorously they can easily grow 6 feet in just 3 months , it's a good idea to add some slow-acting granular fertilizer to especially poor, thin soil. The better their diet, the larger the flowers. Do not overdo the nitrogen because that will delay flowering. Spreading a 2- or 3-inch mulch layer of some kind of organic material on the soil will reduce moisture loss through evaporation and discourage weeds.

While a few sunflower varieties do not need any staking, it is a good idea to support plants that grow over 3 feet tall or are multi-branched. Their branches are fairly brittle, especially at the points where they join the stems. Shallow rooted and weighed down with many large flower heads, plants are vulnerable to summer winds and rain. Tie the plants loosely to stakes with lengths of cloth or other soft material as needed.

Birds and squirrels can be a problem when seeds ripen and harvest time approaches. If you do not plan to use the seeds, it is fun to watch wildlife enjoy the bounty. You may want to cut the flower heads off and lay them out in the sun to dry and provide easier access to wildlife.

Conversely, to deter birds and squirrels, barrier devices are most effective. As seed heads mature and flowers droop, cover each one with white polyspun garden fleece. It will let light and air in and keep critters out. Also try cutting away the few leaves that are closest to the heads to make it harder for birds to perch and feed.

Deer will readily eliminate a sunflower patch. As they favor the new, tender leaves at the top of the plants, a inch chicken wire barrier supported by 6-foot bamboo stakes should keep them at bay. Simply raise the wire as the plants grow. Sunflowers are virtually as care free as their smiling faces suggest. However, they are sometimes infected with fungal diseases such as mildews and rusts. Downy Mildew causes mottling and pale areas on upper leaf surfaces and a fuzzy mold growth on their undersides.

Eventually the leaves wither and die. The oldest leaves are usually infected first. Downy mildew is most likely to occur on cool damp nights and warm humid days. It spreads by means of tiny spores carried to plants and soil by wind and rain or transmitted by garden tools. It will not kill a mature plant; it just mars its appearance. Rust appears on upper leaf surfaces first as yellow or white spots that turn brown or black.

Puffy blisters then appear on the undersides. The disease may spread to stems and flowers causing distorted growth. Rust sometimes spreads to the cultivated sunflowers from weeds such as wild mustard, shepherd's-purse, pigweed, and lamb's-quarters. If fungal diseases are spotted early, spraying with a general garden fungicide as directed on the product label can protect healthy foliage.

Remove and destroy seriously infected plants. Keep the area weeded and clean up plant debris from the garden in the fall. Very tall varieties may need the support of a garden cane — especially when growing in an exposed position. After flowering, leave the faded flower head intact so the birds can feast on the seeds. Once they have eaten their fill pull out the entire plant and put it on the compost heap. After flowering, sunflower heads develop masses of sunflower seed.

You can harvest these to use in cooking, but bear in mind you will need to remove the tough seed coat before eating. Better still, take the seed and leave them to dry for a few days, before storing in a paper envelope in a dry spot, so you can sow them the following year.

Make sure you leave some seeds for the birds, too. Sunflowers are generally trouble free but young seedlings are susceptible to slug and snail damage. If you are only growing a few sunflowers, make sure you let them grow quite tall before planting out. You could also use wildlife-friendly slug pellets or copper tape to deter them. Kick start the festive season and get in touch with your creative side with our minute online class on creating Christmas wreaths with natural materials.

The perfect seasonal addition to your garden, these low-maintenance expertly trained evergreen trees can be enjoyed for years to come. Low-maintenance creeping, hardy carpet Phlox is ideal for colourful, spring ground cover. Home How to Grow plants How to grow sunflowers. This review contains affiliate links and we may receive a commission for purchases made. Please read our affiliates FAQ page to find out more. How to grow sunflowers — where to grow sunflowers.

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Help us achieve our goals Make a donation. Join the RHS today and support our charity Join now. Growing Tips Growing conditions Sunflowers like to grow in full sun in well drained soil.

When to grow See individual seed packets for details. What you need Choose a packet of sunflower seeds — remember to look to see how tall it might grow Gardening gloves A rake A trowel Plant label and pencil How to grow Sunflowers can be sown straight in to the ground where they are going to flower, so make sure the space you are going to sow is weed free, by using a trowel to remove the weeds.

Rake the soil to a fine tilth a fine crumbly texture and make some drills 12mm deep. Leave a 10cm space between each seed. Place the seed in carefully and cover them up with soil. As they grow, if the plants are crowded, then thin them out to about 45cm apart leaving the strongest, tallest plants.