Here's what you need to do in the garden in August

It’s time to harvest some plants and sow others, but whatever you do, don’t take your eyes off your garden during what can be a harsh, hot and dry month. While you’re enjoying the fruits of your labor (hello, tomatoes!), get a jump on next year’s garden by keeping on top of weeds, relocating and dividing perennials, and ordering spring bulbs. And if you’re leaving for vacation, remember to arrange for a surrogate caretaker.

1. The 13th annual Great LI Tomato Challenge is coming! Send your photos and tips to jessica.damiano@newsday.com.

2. Sow seeds of lettuce, radish, spinach, peas and other cool-season crops right into the garden now for a fall harvest.

3. Yank weeds as soon as you notice them; that will prevent them from becoming unmanageable and reduce next year’s population.

4. Deadhead annuals and perennials, and many will put on a second (or third) show.

5. Stop fertilizing trees, shrubs and perennials.

6. Start relocating evergreens, digging up as much of their root systems as possible.

7. Keep watering trees and shrubs, especially those planted this year; they’ll need extra TLC until their first frost.

8. If you haven’t already, get your spring bulb orders in before catalogs sell out of your first choices. They should ship at the right planting time in fall.

9. If cabbage heads are split, bring them indoors as soon as you notice. Those left on the plant will become inedible.

10. Keep mower blades set at 3 inches or higher; grass needs length to photosynthesize and thrive.

11. Don’t let zucchini grow too large; they taste better and are more tender when smaller.

12. For the best taste, let tomatoes ripen on the vine.

13. Apply a liquid seaweed product to hybrid tea roses (follow package instructions) to help prevent heat wilt.

14. Harvest onions when their foliage flops over, cure in a well-ventilated area for 10 days, then store in a cool, dark room.

15. Divide spring bloomers like Japanese and Siberian iris.

16. If houseplants were moved outdoors for summer and are outgrowing their pots, move them into the next size container.

17. Harvest beets when 2 inches wide. Don’t forget, you can saute and eat the foliage, too (don’t try this with leaves of other crops; some will make you sick).

18. If you haven’t sprayed roses, you can use their hips to make tea and jam.

19. Water the lawn deeply when needed instead of sprinkling lightly every day. Aim for a total of 2 inches per week, including rainfall.

20. Remove fallen fruit from around trees, and clear leaves and debris to avoid pest and disease problems.

21. If you want to relocate spring bulbs, transplant them now.

22. It’s time to renovate the lawn! Remove dead patches, aerate, apply compost and seed. Water deeply just once, then sprinkle twice a day.

23. Join me at 7 p.m. for the Great Long Island Tomato Challenge at Farmingdale State College Campus Center, Ballrooms B and C, 2350 Broadhollow Road in Farmingdale. Bring your biggest tomato, and you might be crowned king or queen.

24. Collect seeds from daylilies, Cleomes, rose campions and other podding plants and store in a paper envelope in the fridge, away from fruit, until spring.

25. Move vacationing houseplants and potted tropicals into a shady spot for five days to acclimate them for their move indoors.

26. Divide and transplant peonies, keeping eyes no more than an inch beneath the soil.

27. Monitor container moisture levels at least once daily; potted plants need more water than those growing in the garden.

28. If electrical storms are forecast, remember to turn off pond pumps.

29. Make free plants with cuttings of geraniums and wax begonias, rooted indoors. Care for them as houseplants until spring, then plant outside in pots or directly in the garden.

30. Move houseplants and potted tropicals back indoors until Memorial Day.

31. Re-edge beds to tidy up their appearance.