Planting Out by Apex

From each answer to a clue marked with an asterisk the name of a plant given in Chambers is to be omitted. These clues apply, both by definitions and subsidiary parts, to the full, unmutilated words, whose lengths are indicated by numbers in brackets. No plant is used more than once. Examples:- Clue leads to gorsedd, enter DD: clue leads to boatswain, enter BWAIN: clue leads to Jacobean, enter JACO. All other clues are normal.
Every word is in Chambers Twentieth Century Dictionary 1972 Edition.

Across
1* Investigator of worms develops them on light soil (15)
9 A couple of orchids one planted in tub to order (6)
10* To bind the first of chrysanthemums loosely set in a pot (10)
11* An enthusiast is necessary to hybridize a lotus (6)
12 A spray of erica round a bit of lavender is very sweet (6)
14 Hawk weed absorbs sun and luminance (6)
16 Warm and dry plot that's made to lie on (6)
18 Some groundsel left for hawk (4)
19 Fragments from Scotland, a boy put in empty barrows (5)
22 Premises needed for yield at August (4)
24* Strange fliers nesting among the leaves and chaff (10)
27 A leisurely walk round after the first of September (6)
29 Something to stop the spreading wind in advance (6)
30* Store keeper in charge of hemp (8)
31 Light breeze about to split branch in prickly shrub (5)
32 Solid metallic plate provided to hold. a rambling tree (6)
33* Awfully stenchy, a room coated with yellow fluid of plant-tissues (15)
Down
1* End of March, the rose-laurel about to seed in obscure places (13)
2 Hottish composition a gang piled up around tree (6)
3* Fibre and broken twigs is used for dressing the thatch (9)
4 Derv and paraffin ruining the soil (4)
5 Cut off some lines, about 250 for all to see (7)
6* Birds after yellow cuckoo-flowers (10)
7* Very unpleasant sitting in uncultivated end of garden (8)
8* Immovable raw materials covering the stiff clay (10)
13* Canary lettuce is specially produced for the brave and the fair (14)
15* Structures to support about four rare monuments (8)
17 Tending to escape working yourself, mostly (7)
19 Species of acacia showing rot around the fifth month (6)
20* Opening of outhouse with a handle of bone (6)
21 I'm turning over a place for setting ... (6)
23 ... a small hard seed for fruit (5)
25 Resin produced by yellow climbing plant (5)
26* Machines for cutting slivers about right ... (7)
28*  ... another with blades has one cutting the chaff smooth (9)

To enter the competition send your solution , in list format, to me at derek@crosswordcentre.fsnet.co.uk before the 1st December. The first correct entry picked will win a copy of the top of the range, hardback edition of Chambers Thesaurus  which has been donated by the publishers.